Murakami's Hostile Push at Cosmo Energy, Settled by Iwatani's White-Knight Block Trade
City Index Eleventh and Aya Murakami amass 19.9 percent -> Japan's first majority-of-minority poison-pill vote -> Iwatani buys the entire stake for Y105B (USD 710M)
Background
Yoshiaki Murakami, Japan's original corporate raider
A former METI bureaucrat, Murakami founded MAC Asset Management (widely known as the Murakami Fund) in 1999 and ran activist campaigns through the 2000s against Tokyu, Shoei, Nippon Broadcasting, Hanshin Electric Railway and TBS. He was the first Japanese investor to be feared by domestic boards in the Anglo-American sense, accumulating influence far in excess of his fund size.
2006-2007, insider-trading conviction and de-facto exile
In June 2006 Tokyo prosecutors arrested Murakami on insider-trading charges. The case centred on Livedoor's planned 35 percent stake in Nippon Broadcasting in early 2005; the Murakami Fund had bought NBS shares ahead of public disclosure and booked roughly Y3 billion of gains. The Tokyo District Court sentenced him to two years in prison plus fines and disgorgement of about Y1.15 billion in fines and Y3 billion in confiscation. The sentence was suspended on appeal and the Supreme Court upheld the conviction. The original fund was wound up; Murakami largely disappeared from the public sphere of Japanese activism.
The 2010s comeback through Aya Murakami
In the mid-2010s the Murakami family rebuilt its activist platform through a scatter of vehicles, City Index, Reno, Office Support, South Coast Investment and the Murakami Foundation. Yoshiaki stepped behind the scenes while his eldest daughter Aya Murakami took the public-facing role on filings and press appearances, a deliberately generational pivot. The introduction of Japan's Corporate Governance Code (2015) and Stewardship Code created an environment far more receptive to shareholder voice than the 2000s.
March 2022, entry into Cosmo Energy
The catalyst was Abu Dhabi's IPIC International (now part of Mubadala) selling its remaining roughly 20 percent stake in Cosmo Energy in March 2022. City Index Eleventh and Aya Murakami began buying immediately afterwards. On April 13, 2022 they disclosed a 5.81 percent joint holding under Japan's large-shareholder rule. Cosmo shares jumped roughly 18 percent on the day, the largest one-day gain in the company's listed history. Bloomberg and Nikkei flagged the move as the opening shot of consolidation in Japanese downstream energy.
2023, 20 percent and the hostile-TOB signal
Through late 2022 and the first half of 2023 the Murakami group added to the position, taking it to around 20 percent. They formally pressed Cosmo's board for larger buybacks, a higher dividend, a review of carving out the refining business, and the right to nominate outside directors, with the implied next step a full hostile tender offer. The market began pricing in a Murakami-led TOB as the base case.
June 2023, Japan's first majority-of-minority poison-pill vote
At its June 2023 AGM Cosmo's board tabled a poison-pill renewal (a share-warrant allotment to existing holders that triggers on threshold accumulation by an unwanted bidder). The unusual feature: voting rights of the Murakami group (about 20 percent) were excluded from the tally, a majority-of-minority mechanism more familiar from US MBO and related-party transactions. The vote passed, but Reuters quickly published a calculation showing that with Murakami's votes included support would have dropped to roughly 45 percent, i.e. the pill would have been defeated. Governance experts split sharply on the legitimacy of the exclusion.
July to October 2023, injunction threat and a second vote scheduled
Murakami publicly floated the possibility of seeking a Tokyo District Court injunction against the pill on the grounds that the exclusion was unlawful, and disclosed intent to increase the holding to 24.56 percent. No injunction was ultimately filed. Cosmo, partly in response, called a second EGM for December 14, 2023 to re-approve the pill, this time on a normal one-share one-vote basis, presenting the move as a confidence vote that it could win on a level playing field.
December 1, 2023, Iwatani enters as white knight and Murakami exits
Thirteen days before the December 14 EGM, Japan's industrial-gas leader Iwatani Corp (TSE Prime, ticker 8088) announced it would buy the Murakami group's entire 19.93 percent block at Y6,052 per share, an 8 percent premium to the November 30 close of Y5,616, for Y105.3 billion (USD 710M). Iwatani framed the purchase around synergies in LPG and hydrogen distribution. Murakami issued a notably amicable statement saying it hoped Iwatani's ownership would accelerate Cosmo's efforts to increase shareholder value, and exited the entire position. The December 14 vote went ahead but had become largely procedural.
Deal Summary
- Deal Value
- Y105.3B (Iwatani purchase price, USD 710M)
- Acquirer
- Murakami Group (City Index Eleventh + Aya Murakami) -> exit; Iwatani acquires 19.93 percent
- Target
- Cosmo Energy Holdings Co., Ltd.
- Announced
- Apr 13, 2022 (initial 5.81 percent disclosure)
- Closed
- Dec 1, 2023 (Iwatani block purchase)
- Country
- Japan
Executive Summary
- [Murakami's return] After a seven-year absence following his 2007 insider-trading conviction, Yoshiaki Murakami formally re-entered Japanese activism on April 13, 2022 with a 5.81 percent disclosure on Cosmo Energy by City Index Eleventh and his daughter Aya Murakami. Cosmo shares jumped roughly 18 percent that day, the largest one-day gain in its listed history.
- [Build to 20 percent and a hostile-TOB signal] By H1 2023 the group held about 20 percent, demanding buybacks, dividend increases, a review of carving out the refining business and the right to nominate outside directors, with a hostile TOB clearly on the table.
- [Japan's first majority-of-minority poison-pill vote] At the June 2023 AGM Cosmo passed a pill renewal that excluded Murakami's roughly 20 percent from the tally. A Reuters calculation showed support would have fallen to about 45 percent had Murakami voted, i.e. the pill would have failed under a conventional one-share one-vote count.
- [Iwatani's white-knight block trade] On December 1, 2023, Iwatani Corp bought the full 19.93 percent Murakami block at Y6,052 per share (an 8 percent premium), Y105.3 billion (USD 710M) in total, citing LPG and hydrogen synergies. The transaction neutralised both the December 14 EGM and the lingering injunction threat at a single stroke.
- [Murakami's premium exit] The Murakami group sold its entire position and issued a supportive statement. Market estimates suggest a roughly 2.5-3.0x return on entry prices struck in 2022, a textbook Murakami 2.0 outcome: accumulate, demand, exit on a premium rather than press for control.
- [A new chapter in Japanese poison-pill case-law] Where the 2007 Bull-Dog Sauce vs Steel Partners ruling established that a pill could be lawful if approved by shareholders, the Cosmo case shows that the legitimacy of a pill can be secured by vote design and a white-knight block trade rather than by a court ruling. The exclusion-vote question itself was never tested in court.
- [A signal for Japanese downstream energy] Cosmo is the number-three refiner in Japan behind ENEOS and Idemitsu Kosan, with about 12 percent market share. The Murakami campaign accelerates the broader narrative of capital-efficiency activism in Japanese refining, where structural overcapacity meets large free cash flow.
- [A template repeated in 2025] The same pattern (accumulate, demand, exit through buybacks or a friendly counterparty) reappeared in Murakami's 2025 campaign against Fuji Media Holdings, where a Y1.5 billion buyback ended a year-long battle. Cosmo Energy is the proof of concept.
Industry Overview
Japanese downstream oil refining is a three-player oligopoly: ENEOS Holdings (about 50 percent share), Idemitsu Kosan (about 30 percent) and Cosmo Energy (about 12 percent). The market is in structural decline thanks to falling gasoline demand, an aging population and an accelerating EV transition, even as cyclical refining margins remain volatile. The combination of shrinking volumes and persistent free cash flow makes the sector a classic target for capital-efficiency activism. Cosmo had been without a controlling shareholder since IPIC unwound its joint venture in 2015, and the final IPIC exit in March 2022 opened the door for Murakami.
Cosmo revenue (FY2022)
~Y3.06T
boosted by oil-price surge
Cosmo market cap (late Nov 2023)
~Y475.5B
based on ~Y5,616 share price
Cosmo refining market share
~12 percent
number three behind ENEOS and Idemitsu
Cosmo Eco Power renewables
~250MW onshore wind
Vision 2030 target 600MW
Cosmo Energy Holdings sits atop Cosmo Oil (refining), Cosmo Oil Marketing (about 2,700 service stations), Cosmo Energy E&P (upstream) and Cosmo Eco Power (renewables, mainly onshore wind). The activist thesis combined refining free cash flow being returned via buybacks with the option value embedded in Cosmo Eco Power, which had been masked inside a refiner's holding structure.
Key Players
Company Overview: Cosmo Energy Holdings Co., Ltd.
Cosmo Energy Holdings was created in 1986 through the merger of Daikyo Oil, Maruzen Oil and Asia Oil, and adopted a holding-company structure in 2015. It is listed on the TSE Prime market under code 5021. Refining accounts for about 85 percent of revenue, but the activist case hinged on the value of the renewables platform (Cosmo Eco Power) and the hydrogen-station optionality of the service-station network, which the market argued were under-monetised within a refiner's wrapper. The dissolution of the IPIC joint venture in 2015 and IPIC's final exit in 2022 left Cosmo with an unusually long period of no controlling shareholder, creating the opening Murakami exploited.
Revenue (FY2022, oil-price boom)
~Y3.06T
crude-price tailwind
Revenue (FY2018, cycle trough)
~Y2.51T
compressed refining margins
Refining share of revenue
~85 percent
Cosmo Oil plus Marketing
Service-station network
~2,700
third largest in Japan
Revenue by Segment (FY2022)
FY2022 mix; market estimates. Refining dominates today, but the activist value lever was always [separating, or at least re-rating, the renewables and upstream segments].
Control Battle Overview
The Cosmo case is now the canonical example of modern Japanese activism playing out as a staged 22-month standoff between an accumulating activist and a board willing to combine an aggressive pill with a friendly block-trade exit. There is no single winner, which is part of why both sides treat the outcome as a model.
March 2022, when Abu Dhabi's IPIC International sold its residual roughly 20 percent stake in Cosmo Energy and effectively created a controlling-shareholder vacuum. Within weeks Murakami's City Index Eleventh and Aya Murakami had started buying, with the April 13, 2022 5.81 percent disclosure opening the formal campaign.
📈 Price Impact
Cosmo shares went from roughly Y2,000-2,500 just before Murakami's entry, +18 percent on the April 13, 2022 disclosure, to about Y4,200 around the June 2023 pill vote, and printed at Y6,052 in the Iwatani block trade on December 1, 2023. After Murakami's exit Cosmo stabilised in the Y4,500-5,000+ range as the board adopted parts of the activist agenda, leaving a roughly 150-200 percent re-rating over 22 months.
🗡️ Battle Timeline
5.81 percent disclosure, Murakami's return to Japan
City Index Eleventh and Aya Murakami jointly disclose a 5.81 percent stake in Cosmo Energy. Cosmo shares jump roughly 18 percent on the day, the largest one-day gain in the company's listed history. The biggest single Murakami-linked filing since the 2007 conviction.
Build to roughly 20 percent and table the demand list
Through late 2022 and H1 2023 Murakami pushes the position to about 19.9-20 percent and formally tables demands for larger buybacks, a higher dividend, a review of carving out the refining business and outside-director nominations. The market starts pricing a hostile TOB as base case.
First majority-of-minority poison-pill vote in Japan
At the AGM Cosmo renews its share-warrant poison pill with Murakami's roughly 20 percent excluded from the vote. The pill passes; Reuters calculates that with Murakami's votes included support would have been about 45 percent. The exclusion design is unprecedented for a Japanese listed-company pill vote.
Injunction threat plus filing to lift stake to 24.56 percent
Murakami publicly signals that the exclusion may be unlawful and that it could seek a Tokyo District Court injunction, while disclosing intent to increase the stake to 24.56 percent. The injunction is never formally filed, but the threat keeps the Bull-Dog Sauce precedent line in play through the autumn.
Call a December 14 EGM, drop the exclusion
Cosmo announces an EGM for December 14, 2023 to re-approve the pill, this time on a normal one-share one-vote basis. The move acknowledges the legitimacy questions around the June vote and positions the board as confident it can win on level terms, though the result is not seen as a foregone conclusion.
White-knight block trade, 19.93 percent at +8 percent premium
Iwatani announces it will buy the entire 19.93 percent Murakami block at Y6,052 per share (+8 percent to the November 30 close of Y5,616), Y105.3 billion (USD 710M) in total, citing LPG and hydrogen synergies with Cosmo's service-station network and refining assets. Murakami issues a notably amicable statement and exits the position in full.
EGM held, vote procedural after Murakami exits
The EGM proceeds as scheduled but with the principal counterparty already gone. The pill renewal becomes essentially procedural, and market attention shifts to the contours of the Cosmo-Iwatani relationship.
5.81 percent disclosure, Murakami's return to Japan
City Index Eleventh and Aya Murakami jointly disclose a 5.81 percent stake in Cosmo Energy. Cosmo shares jump roughly 18 percent on the day, the largest one-day gain in the company's listed history. The biggest single Murakami-linked filing since the 2007 conviction.
Build to roughly 20 percent and table the demand list
Through late 2022 and H1 2023 Murakami pushes the position to about 19.9-20 percent and formally tables demands for larger buybacks, a higher dividend, a review of carving out the refining business and outside-director nominations. The market starts pricing a hostile TOB as base case.
First majority-of-minority poison-pill vote in Japan
At the AGM Cosmo renews its share-warrant poison pill with Murakami's roughly 20 percent excluded from the vote. The pill passes; Reuters calculates that with Murakami's votes included support would have been about 45 percent. The exclusion design is unprecedented for a Japanese listed-company pill vote.
Injunction threat plus filing to lift stake to 24.56 percent
Murakami publicly signals that the exclusion may be unlawful and that it could seek a Tokyo District Court injunction, while disclosing intent to increase the stake to 24.56 percent. The injunction is never formally filed, but the threat keeps the Bull-Dog Sauce precedent line in play through the autumn.
Call a December 14 EGM, drop the exclusion
Cosmo announces an EGM for December 14, 2023 to re-approve the pill, this time on a normal one-share one-vote basis. The move acknowledges the legitimacy questions around the June vote and positions the board as confident it can win on level terms, though the result is not seen as a foregone conclusion.
White-knight block trade, 19.93 percent at +8 percent premium
Iwatani announces it will buy the entire 19.93 percent Murakami block at Y6,052 per share (+8 percent to the November 30 close of Y5,616), Y105.3 billion (USD 710M) in total, citing LPG and hydrogen synergies with Cosmo's service-station network and refining assets. Murakami issues a notably amicable statement and exits the position in full.
EGM held, vote procedural after Murakami exits
The EGM proceeds as scheduled but with the principal counterparty already gone. The pill renewal becomes essentially procedural, and market attention shifts to the contours of the Cosmo-Iwatani relationship.
🔩 Key Instruments
⚔️ Offense Playbook— Murakami Group + City Index Eleventh
From 5.81 percent to roughly 20 percent over about 18 months, with the timing of disclosures calibrated to maximise market impact while controlling average entry cost.
Escalating asks (buybacks, dividend, refining carve-out, outside directors) layered with the filed intent to push to 24.56 percent, putting a hostile bid within reach without committing to it.
Public floats of a Tokyo District Court challenge to the exclusion vote. Never filed, but credible enough to keep the legal-risk premium priced into Cosmo's defence calculus through autumn 2023.
🛡️ Defense Playbook— Cosmo Energy board (and Iwatani as white knight)
Japan's first listed-company pill renewal that excluded the unwanted bidder from the vote tally. Pushed the boundary of acceptable defence design and arguably created a new template, though the legal question was never resolved in court.
Thirteen days before the EGM, the entire Murakami block was sold to a friendly industrial-gas major at an 8 percent premium. Resolved the EGM, the injunction risk and the longer-term hostile-TOB threat in a single transaction.
Turning Point
2023-12-01Iwatani's 19.93 percent white-knight block trade
The pivot of the entire 22-month arc. With the December 14 EGM thirteen days away and the injunction threat still live, Iwatani's purchase of the full Murakami block at an 8 percent premium collapsed the dispute before the vote took place. The case is now remembered not as one in which a Japanese court upheld a poison pill, but as one in which a pill plus a white knight together rendered the legal question moot. Coverage in Nikkei and the financial press routinely describes it as the first major instance of Murakami voluntarily exiting a target without a court fight.
Final Verdict
DrawDraw, Murakami takes the return, Cosmo keeps independence, Iwatani gets strategic shareholding
Margin: Murakami: estimated 2.5-3.0x return / Cosmo: hostile bid averted / Iwatani: largest shareholder plus LPG and hydrogen synergies
Hard to declare a single winner. Murakami did not get control but executed its declared strategy of premium exit over conquest. Cosmo carried the governance baggage of the exclusion vote but kept its independence and re-anchored its shareholder base to a long-term industrial partner. Iwatani paid an 8 percent premium for a single-largest stake and a multi-decade synergy partner. The Japanese activism market took away the lesson that the legitimacy of a poison pill can be secured by vote design and white-knight matchmaking, not just by court rulings.
Deal Structure
The structure unfolded in four acts: staged accumulation by Murakami -> escalating governance demands -> Cosmo's majority-of-minority poison-pill vote -> Iwatani white-knight block trade. The transaction that closed was not between Murakami and Cosmo but between Murakami and Iwatani, with Cosmo's capital structure unchanged in legal terms but its largest shareholder swapped.
Pre-Deal
Murakami Group
City Index Eleventh + Aya
Cosmo Energy
TSE Prime 5021
Public float
Institutional and retail
Post-Deal
Iwatani Corp
White knight; largest holder
Cosmo Energy
Independent
Public float
~80 percent
Key Terms
Advisors
Three advisory lines ran in parallel: the Murakami group's in-house team supported by Japanese counsel, Cosmo's domestic IB and law firm, and Iwatani's own house team. Public disclosure is light; the lineup below reflects Nikkei reporting and market consensus.
Murakami Group (City Index Eleventh) Advisors
Murakami Group in-house
Strategy and execution (in-house)Position sizing, accumulation pace, framing of governance demands; Aya Murakami fronted filings and press
Nishimura & Asahi (market reporting)
Legal counselReviewed the legality of Cosmo's majority-of-minority vote and supported the (ultimately unfiled) injunction threat
Cosmo Energy / Iwatani (white knight) Advisors
Nomura Securities
Cosmo financial adviserPoison-pill design, white-knight matchmaking, shareholder communications (market reporting)
Mori Hamada & Matsumoto
Cosmo legal counselShare-warrant allotment structure and defence of the majority-of-minority vote
Iwatani in-house + Sumitomo Mitsui Banking
Iwatani financial adviserFunding for the Y105.3B block trade and the LPG/hydrogen-synergy investment case
Adviser lineup is based on Nikkei and market reporting; some entries are unconfirmed. Neither Murakami nor Iwatani disclosed advisers in their official statements.
Financials
Unit: hundreds of millions of yen. FY runs April through March. FY2020 operating loss reflects Covid-era demand collapse; FY2022 captures the post-Ukraine refining-margin spike. EBITDA and SG&A include market estimates. Source: Cosmo Energy securities filings and Nikkei.
| Item | FY2018 | FY2019 | FY2020 | FY2021 | FY2022 |
|---|---|---|---|---|---|
| Revenue | Y 25,100hundreds of millions of yen | Y 25,800hundreds of millions of yen | Y 19,500hundreds of millions of yen | Y 24,400hundreds of millions of yen | Y 30,600hundreds of millions of yen |
| COGS | Y 23,000hundreds of millions of yen | Y 23,800hundreds of millions of yen | Y 18,500hundreds of millions of yen | Y 22,000hundreds of millions of yen | Y 27,700hundreds of millions of yen |
| Gross Profit | Y 2,100hundreds of millions of yen | Y 2,000hundreds of millions of yen | Y 1,000hundreds of millions of yen | Y 2,400hundreds of millions of yen | Y 2,900hundreds of millions of yen |
| SG&A | Y 1,400hundreds of millions of yen | Y 1,500hundreds of millions of yen | Y 1,300hundreds of millions of yen | Y 1,500hundreds of millions of yen | Y 1,700hundreds of millions of yen |
| Operating Income | Y 700hundreds of millions of yen | Y 500hundreds of millions of yen | Y -300hundreds of millions of yen | Y 900hundreds of millions of yen | Y 1,200hundreds of millions of yen |
| EBITDA | Y 1,200hundreds of millions of yen | Y 1,000hundreds of millions of yen | Y 300hundreds of millions of yen | Y 1,500hundreds of millions of yen | Y 1,900hundreds of millions of yen |
| EBITDA Margin | 4.8% | 3.9% | 1.5% | 6.1% | 6.2% |
Valuation
Market estimates put Murakami's average entry cost at roughly Y2,000-2,500 per share in the spring of 2022, in the window immediately after the IPIC sale. The exit at Y6,052 per share to Iwatani in December 2023 implies a 2.5-3.0x return on the 19.93 percent block, with roughly Y105.3 billion of cash proceeds. Adding earlier sales into the market on the way up, the campaign's overall IRR is widely estimated above 60 percent. The Iwatani price implies an EV/EBITDA on FY2022 EBITDA of about 5.5-6.0x, broadly in line with global refining peers but cheap if Cosmo Eco Power is valued separately on renewables multiples.
| Metric | Value | Notes |
|---|---|---|
| Cosmo share price (Mar 2022, around IPIC exit) | ~Y2,000-2,500 | estimated Murakami entry range |
| Cosmo share price (Apr 13, 2022 disclosure) | ~Y2,800 | +18 percent on the day, record one-day gain |
| Cosmo share price (Jun 2023 poison-pill vote) | ~Y4,200 | activism premium priced in |
| Cosmo share price (Nov 30, 2023, Iwatani -1) | Y5,616 | reference price for the +8 percent premium |
| Iwatani purchase price | Y6,052/share | +8 percent premium |
| Iwatani total consideration (19.93 percent) | ~Y105.3B (USD 710M) | All cash; announced Dec 1, 2023 |
| Estimated Murakami return multiple | ~2.5-3.0x | vs estimated average entry price (market estimate) |
| Implied EV/EBITDA at Iwatani price | ~5.5-6.0x | Based on FY2022 EBITDA of ~Y190B and estimated net debt |
Murakami's average entry price, total invested capital and realised IRR were never publicly disclosed; figures above are based on Bloomberg and Nikkei reporting and point-in-time share prices.
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Deal Rationale
Murakami Group's playbook
- [Controlling-shareholder vacuum + capital-efficiency gap] After the IPIC exit Cosmo had no controlling holder, traded below book and was generating sizeable refining cash flow with under-sized buybacks, a textbook Japanese activism setup.
- [Refining cash flow plus renewables option value] The thesis combined a buyback/dividend campaign on the refining cash flow with a re-rating case for Cosmo Eco Power, separately valued, potentially carved out.
- [The 20 percent threshold] At about 20 percent the group sat just under the one-third special-resolution blocking line but already had de-facto veto power over major board actions. The implicit threat of a hostile TOB at 25 percent created leverage without committing to a full bid.
- [Premium exit, not control] In a clear break from the 1990s playbook, Murakami structured the campaign so that the natural exit was a white-knight block trade or a buyback at a premium, not a takeover. This is the post-2007 Murakami 2.0 signature.
- [Aya Murakami as the public face] Putting Aya on filings and at press conferences signalled to the market that this was a governance activist, not a corporate raider, and gave Cosmo's board a reputational off-ramp for engaging.
Cosmo board and Iwatani as white knight
- [Cosmo's dual defence: pill plus white knight] Rather than rely on the pill alone, the board ran a parallel track to line up a friendly long-term holder. The combination, majority-of-minority pill in June plus Iwatani block trade in December, rendered the hostile-bid threat moot without ever litigating the exclusion question.
- [Iwatani's strategic logic] Iwatani is Japan's largest industrial-gas player and a leader in the hydrogen-station rollout. Cosmo's 2,700-station network and refining assets are direct synergy partners for LPG distribution and hydrogen supply. A 19.93 percent stake delivers single-largest-shareholder status without triggering a tender-offer obligation.
- [Why the 8 percent premium made sense] The premium is the cost of removing Murakami before the December 14 EGM and closing off the injunction risk in a single step. Cheap, in context, relative to the value of preserving independence and the LPG/hydrogen optionality.
- [Precedent value of the majority-of-minority vote] The mechanism itself, even though never tested in court, is now part of the Japanese defence toolkit. Future targets can argue that an unwanted bidder is a related party for the purposes of a pill vote.
- [Cosmo absorbs part of the activist agenda] After Murakami exited Cosmo announced larger buybacks and revised its mid-term plan, formally beating the activist while informally adopting parts of its demand list. A characteristic pyrrhic-victory outcome for Japanese boards.
Post-Deal Assessment (June 2026 as of)
The campaign closed cleanly on December 1, 2023 with the Iwatani block trade. Murakami's group exited at a substantial multiple on its entry; Cosmo kept its independence under the umbrella of a friendly long-term industrial partner; Iwatani locked in a strategic shareholding and a multi-decade LPG/hydrogen partner. The case has since become the most cited Japanese activism precedent post-Bull-Dog Sauce, both for its defence architecture (majority-of-minority vote plus white knight) and for its activist economics (premium exit rather than full control). The same Murakami 2.0 pattern was visible again in the 2025-2026 Fuji Media Holdings campaign, which ended with a roughly USD 1.5 billion buyback.
Positives
- [Murakami] Realised an estimated 2.5-3.0x return without ever launching a tender offer, and rebuilt its market standing under Aya Murakami's leadership.
- [Cosmo] Defended independence while quietly adopting part of the activist agenda through buybacks and a revised medium-term plan, a textbook pyrrhic victory outcome.
- [Iwatani] Paid an 8 percent premium for a single-largest-shareholder seat and direct access to Cosmo's 2,700-station network for LPG and hydrogen distribution.
- [Japanese market] Now has a working precedent for pill + majority-of-minority + white knight, a defence package other listed boards can adapt.
Risks & Concerns
- [Governance debate] The legitimacy of the June 2023 exclusion vote was never tested in court; future activists are likely to challenge the same design.
- [Cosmo] Iwatani's 19.93 percent stake makes it the single largest shareholder; this constrains Cosmo's strategic autonomy and could complicate any future consolidation discussion with ENEOS or Idemitsu.
- [Murakami] The premium exit over control strategy maximises short-term returns but invites criticism that it does not deliver long-run governance change.
- [Refining sector] Cosmo's structural disadvantages versus ENEOS and Idemitsu (sub-scale upstream, smaller retail footprint) remain; the medium-term consolidation question has been deferred, not answered.
This announcement appears as a matter of record only
Murakami Group (City Index Eleventh)
Acquirer
Cosmo Energy Holdings Co., Ltd.
Target
Murakami Group's Hostile TOB Push at Cosmo Energy, Settled by Iwatani's White-Knight Block Trade
Transaction Size
Y105.3B (Iwatani exit price, 19.93 percent)
USD 710M
EV / EBITDA
~5.5-6.0x (implied at Iwatani price)
Multiple
Closed
Dec 1, 2023 (Iwatani block trade)
Deal Date
Editor's Note
The Cosmo case is best read as the precedent that established the legitimacy of a poison pill in Japan now rests on vote design and white-knight matchmaking, not on a court ruling. Murakami chose return over control; Cosmo carried the governance cost of the exclusion vote in exchange for independence. Adviser identifications and Murakami's return economics rely on Nikkei, Bloomberg and market reporting; primary disclosure on those points is limited. Drafted with information available as of June 2026.
Key Concepts in This Deal
The post-2007 reconstitution of the Murakami platform via City Index, Reno, Office Support and other family vehicles, with Aya Murakami in the public-facing role. Cosmo Energy is the campaign that established the template.
Former METI bureaucrat, founder of MAC Asset Management in 1999, lead activist on Tokyu, Hanshin, Nippon Broadcasting and others in the 2000s, convicted of insider trading in 2007 (sentence later suspended), back via family vehicles from the late 2010s.
Hostile listed-company tender offers remain rare in Japan but have become more frequent since the 2015 Corporate Governance Code. Murakami's Cosmo campaign signalled but never formally launched a TOB, instead resolving via a white-knight block trade.
The 2007 Bull-Dog Sauce vs Steel Partners Supreme Court ruling established that a poison pill could be lawful if approved by shareholders. The Cosmo case extends the practical line: the legitimacy of a pill can be secured by vote design and white-knight matchmaking, without a fresh court ruling.
Under Japan's Companies Act the special-resolution blocking line sits at one-third (33.4 percent), but a holding of around 20 percent already delivers de-facto influence over board nominations, mergers and capital-return policy. Murakami deliberately stopped just below the formal blocking line in this case.
A vote tabulated only among shareholders who are not interested parties; common in US MBOs and related-party deals. Cosmo's June 2023 pill renewal excluded the Murakami group's roughly 20 percent, an extraordinary application of the mechanism in a Japanese listed-company defence vote.
A defensive move in which an unwanted shareholder's entire stake is sold to a friendly long-term holder in a single transaction. Iwatani's 19.93 percent block trade at +8 percent is the textbook example for Japan.
The ENEOS-Idemitsu-Cosmo refining oligopoly combines structural decline with high free cash flow, a profile that draws capital-efficiency activism. Murakami's Cosmo campaign is the inflection point for the sector.
Frequently Asked Questions
Did the Murakami group actually take control of Cosmo Energy?
[No.] Between April 2022 and mid-2023 Murakami's vehicles built a roughly 20 percent stake and openly signalled a hostile TOB, but on December 1, 2023 Iwatani Corp bought the entire 19.93 percent block at Y6,052 per share (an 8 percent premium), Y105.3 billion (USD 710M) in total. Murakami exited the position in full, in line with the post-2007 [premium exit over conquest] template that now defines its strategy.
Why was the majority-of-minority poison-pill vote so controversial?
Two reasons. First, it was the first time a Japanese listed-company pill was approved with the unwanted bidder excluded from the vote tally, a mechanism imported from US related-party transactions. Second, Reuters calculated that with Murakami's roughly 20 percent included, support would have fallen to about 45 percent, meaning the pill would have been defeated under a conventional count. Cosmo's CEO argued the design was justified because an interested party should not vote on its own pill. Murakami threatened a Tokyo District Court injunction but never filed, so the question of whether such exclusion is lawful in Japan was never tested.
Why did Iwatani step in, and was the 8 percent premium worth it?
Three reasons. First, [strategic fit]. Iwatani is Japan's largest industrial-gas and LPG company and a leader in the rollout of hydrogen stations; Cosmo's 2,700 service stations and refining assets are direct synergy partners. Second, [largest-shareholder status]. A 19.93 percent stake gave Iwatani the single largest holding without triggering a mandatory tender. Third, [neutralising legal and political risk]. The 8 percent premium (about Y8 billion above market) was effectively the cost of removing the December 14 EGM risk and the lingering injunction threat in one move, modest relative to the strategic value.
How does the 2007 insider-trading case affect how Murakami now operates?
[Indirectly but deeply.] In 2006 prosecutors arrested Murakami over trading in Nippon Broadcasting shares ahead of Livedoor's planned 35 percent stake disclosure. The Tokyo District Court sentenced him to two years and roughly Y1.15 billion in fines and Y3 billion in confiscation in 2007; the sentence was suspended on appeal. The Murakami Fund was wound up and he largely withdrew from public activism. The Murakami 2.0 era reflects that history in three ways: [Aya Murakami fronts public communications]; [the strategy favours premium exits over outright control]; and [legal escalation is used as leverage but rarely pursued]. All three are visible in the Cosmo case.
What is the lasting impact of the Cosmo case on Japanese activism?
Three things. First, a [triple-layered defence template], poison pill plus majority-of-minority vote plus white knight, that other Japanese boards can replicate. Second, a clear [Murakami 2.0 playbook]: accumulate to about 20 percent, escalate governance demands, exit at a premium via a friendly counterparty or a buyback, repeated in the 2025-2026 Fuji Media Holdings campaign. Third, a [meaningful uptick in capital-efficiency pressure on Japanese downstream energy], with Cosmo's experience now part of every refining and utility board's risk inventory.
How much money did the Murakami group make on the campaign?
[There is no official disclosure, but market estimates put the return at roughly 2.5-3.0x.] Murakami's average entry price is generally estimated at around Y2,000-2,500 per share in the spring of 2022, just after the IPIC exit. Selling the 19.93 percent block to Iwatani at Y6,052 per share implies a 2.5-3.0x return on that block, with about Y105.3 billion (USD 710M) of cash proceeds. Adding earlier sales into the market on the way up, the overall campaign IRR is widely estimated above 60 percent. All figures are market estimates; entry price, total capital invested and realised IRR were never publicly disclosed.
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Sources & Notes
- [1]Bloomberg, Cosmo Energy Jumps Most on Record as Murakami Fund Takes Stake (Apr 2022)
- [2]Nikkei Asia, Murakami-linked fund emerges with biggest stake in Cosmo Energy (Apr 2022)
- [3]Japan Times, Cosmo CEO says controversial vote tactics justified in activist defense (May 2023)
- [4]Nikkei Asia, Controversial vote helped Japan's Cosmo prevail on poison pill (Jun 2023)
- [5]Reuters via MarketScreener, Japan Cosmo's poison pill may have failed without uncommon vote (Jun 2023)
- [6]Japan Times, Cosmo calls another shareholder vote in activist defense (Oct 2023)
- [7]Japan Times, Cosmo braces for poison pill anti-activist vote (Nov 2023)
- [8]Reuters via MarketScreener, Iwatani emerges as Cosmo white knight with $710M share buy (Dec 1, 2023)
- [9]DealStreetAsia, Iwatani to buy 19.9 percent stake in Cosmo Energy from Murakami funds (Dec 1, 2023)
- [10]Japan Times, Iwatani emerges as potential Cosmo white knight (Dec 1, 2023)
- [11]Nikkei Asia (Opinion), Yoshiaki Murakami's Cosmo Energy bet defies conventional wisdom
- [12]Nikkei Asia (Opinion), Cosmo Energy's anti-Murakami poison pill won't improve value
- [13]Wikipedia, Yoshiaki Murakami
- [14]Japan Times, Murakami given two-year sentence (Jul 2007)
- [15]Bloomberg, Activist Investors Like Murakami Are Pushing Japan's Stock Market Higher (Sep 2025)
- [16]Cosmo Eco Power official site