ArbLens Weekly: Top 6 Merger Arbitrage Deals by Spread
A snapshot of the six widest merger arbitrage spreads in the current deal universe — with current status, key risks, and what to watch next. Spreads update nightly at arblens.com.
The merger arb landscape in May 2026 is defined by one recurring theme: regulatory uncertainty is the spread driver, not financing risk or shareholder conviction. Four of the six deals below have already received overwhelming shareholder approval. The votes are done. What's keeping spreads wide is the unpredictable timeline of government regulators — a rail regulator in Washington, an insurance commission in Albany, a golden share decision in Jerusalem, and the FCC in a satellite deal that touches Apple's iPhone.
That's the environment. Here's where the opportunities sit.
Shareholders voted 97.4% in favour on April 30. The deal is done on the shareholder side. The 36.9% spread exists entirely because of one gating factor: the Israeli government must formally consent to the transfer of its Special State Share — the "Golden Share" — to FIMI, an Israeli private equity firm that will own New ZIM's domestic operations.
A wrinkle emerged in May: Israeli businessman Haim Sakal submitted a rival $37.50/share bid ($4.5B total). The ZIM board confirmed the Hapag-Lloyd agreement is legally binding and cannot be superseded — the break-fee window for superior proposals expired with the shareholder vote. But the Sakal bid matters anyway: it establishes a credible value ceiling 7% above the current offer and signals that serious Israeli capital views ZIM as worth more than $35. That's a floor-and-ceiling dynamic that changes the risk profile.
Brad Jacobs is acquiring TopBuild — the #1 US insulation installer — for $8.2B via his building products roll-up vehicle QXO. The deal structure is important to understand: shareholders can elect $505 cash or 20.2 QXO shares, but elections are subject to a 45% cash / 55% stock proration cap. In practice, most holders will receive a blended mix regardless of their election choice.
This means the spread is dynamic — the implied value moves daily with QXO's stock price. At QXO $25: implied = $227.25 cash + 11.11 shares × $25 = $505. The 26% spread reflects: HSR not yet filed, QXO shareholder vote required for share issuance (Jacobs is conflicted and cannot vote his own shares), and three simultaneous integrations at QXO (Beacon Roofing, Kodiak, TopBuild). The $600M reverse break fee is backstop protection.
The backstory here is one of the most competitive public M&A processes in recent memory. Netflix originally agreed a deal at $27.75/share. Paramount launched a hostile bid at $30, then raised to $31. Netflix walked away February 26. WBD's board chose Paramount's $31 offer — and shareholders approved it 99%+ on April 23. DOJ cleared February 19. No US antitrust obstacle remains.
The remaining spread is almost entirely a UK CMA bet. A formal inquiry launched in April with the public comment period closing April 27. The CMA's Phase 1 decision is expected within 40 working days. A Phase 2 referral would add 6-9 months and push close into 2027. Financing is fully locked ($43.6B equity, $54B committed debt) with a $7B termination fee payable by Paramount if regulators block.
The largest railroad merger in US history (~$112B) and the longest-duration deal in this list. NSC shareholders approved 99% in November 2025 — an overwhelming mandate. The STB (Surface Transportation Board) rejected the initial filing in January 2026 as procedurally incomplete. Union Pacific refiled April 30, 2026 — restarting the formal review clock.
Under enhanced merger standards for Class I railroads, the STB process typically takes 15+ months from a complete filing. That puts a final decision in mid-to-late 2027 at the earliest. The 13.8% spread is appropriate compensation for a long hold with an opaque regulatory process — but investors must be comfortable with the timeline. The $2.5B reverse termination fee provides downside protection.
The structurally cleanest deal in this group. Shareholder vote passed February 2026. No antitrust concerns — this is an insurance company acquisition, not a horizontal merger. The acquirer (Aquarian Capital, insurance-focused PE) knows exactly what it's buying and has the regulatory experience to navigate state insurance commissions.
The spread exists because multi-state insurance regulatory approvals — particularly the New York DFS — are notoriously slow and follow no fixed timeline. DFS reviews typically run 12-18 months. The 11.9% spread is not pricing deal failure risk. It's pricing regulatory calendar uncertainty. Timeline is the risk, not deal collapse.
The most strategically distinctive deal in this group. Amazon is acquiring Globalstar's globally harmonised L-band and S-band spectrum — the regulatory asset that enables direct-to-device satellite connectivity on standard smartphones. This is spectrum SpaceX cannot replicate: Starlink's frequency allocations don't carry the same global ITU harmonisation. Amazon Leo needs this to compete on D2D.
The deal resolved a major structural complication simultaneously: Apple owns 20% of Globalstar and reserved 85% of its network capacity for iPhone Emergency SOS. Amazon announced a new long-term Apple connectivity agreement at the same moment as the acquisition — turning Apple from a blocking party into a committed long-term partner. No GSAT shareholder vote is required: Thermo Funding (57.6% holder) approved by written consent on April 13.
Live spreads, spread history charts, and full deal analysis — including background, investment thesis, key risks, and catalyst — for every deal in the tracker.
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