This roundup reviews the largest U.S. merger and acquisition developments from September through October 2026, with the legal and regulatory questions each transaction raises.

The defining transaction of the period closed on October 7: Paramount, owned by Skydance, completed its $81 billion acquisition of Warner Bros. Discovery, creating a single Hollywood giant operating under the Skydance name, led by David Ellison with Ynon Kreiz as co-CEO.

The path to closing is as instructive as the deal itself. DOJ concluded the combination would not harm competition or consumers in June. The European Union cleared the transaction in July subject to conditions. A federal judge paused closing for two weeks in July after twelve states challenged the deal on competition grounds, and the states settled their lawsuit in late September, clearing the final hurdle. Warner shareholders had approved the transaction in April.

The lesson for large acquirers: a multi-jurisdiction approval map — DOJ, EU, state attorneys general, and sectoral regulators such as the FCC — must be planned as a single integrated calendar, not as parallel workstreams.

On October 29, alongside third-quarter results, DoorDash announced a proposed $17 billion acquisition of Instacart, combining the two largest third-party delivery platforms in the United States.

The legal issues to watch:

• Antitrust review. Analysts and press coverage expect FTC scrutiny. The combined entity would dominate restaurant delivery and grocery delivery simultaneously, and the agencies will examine overlapping merchant relationships and advertising businesses.
• Political dimension. New York City's mayor publicly criticized the deal, arguing it would mean higher prices and greater economic inequality for gig workers — a reminder that consumer-facing combinations now attract local political engagement, not just federal review.
• Financing and execution. Deal financing, integration costs, and elevated spending are the risks analysts flagged after the announcement.

For any acquirer in the platform economy, the transaction confirms that labor classification, seller economics, and pricing-power arguments are now central to merger review, not peripheral.

On October 20, Elon Musk hinted at a possible combination of Tesla and SpaceX, and on October 21 Tesla reported a drop in quarterly profit as it prepares for a possible merger with Musk's other public company. Wall Street is already modeling a combined entity.

A combination of this kind raises governance questions that rarely appear in ordinary M&A: conflicts of interest involving a controlling shareholder on both sides, special-committee and fairness-opinion mechanics, minority-shareholder protections, and disclosure obligations around related-party transactions. Companies advising founder-controlled groups should expect these issues to dominate the process timeline.

Caesars Entertainment stockholders approved the nearly $6 billion merger with Tilman Fertitta's group on September 23, advancing the sale of the Las Vegas Strip icon toward closing. Gaming-sector transactions continue to carry a second approval layer — state gaming commissions — that materially shapes closing timelines and interim-operating covenants.

• Union Pacific–Norfolk Southern. The $85 billion railroad combination remains in the Surface Transportation Board review process; Union Pacific secured Canadian National's support for the plan in July, and the public-interest review will stretch well into 2027.
• NextEra–Dominion. The utilities seeking to merge committed in September to extend Virginia residents' bill credits and add jobs — evidence that state-level commitments are being used to de-risk federal review of power-sector consolidation driven by AI-driven electricity demand.

M&A activity is being matched by listing activity. Anthropic filed for its IPO on October 27 in what could be a record-breaking debut, and its filing has already re-energized the AI trade. For cross-border investors, the re-opening of large listings changes exit and financing math for pending acquisitions as much as any single deal does.

The quarter's largest Turkish-linked transaction also advanced: on October 28, Yıldız Holding signed a definitive agreement to acquire a controlling interest in a U.S.-based snacks and confectionery manufacturer, with an HSR filing made October 21 and closing targeted for mid-December 2026. Turkish acquirers should note the sequencing the parties used — regulatory strategy and financing structured before signing — and the December congestion now forming in year-end closing calendars.

Three themes define the period: mega-deals are closing (Paramount proves the multi-agency path is navigable), platform-economy deals are politically charged (DoorDash–Instacart), and founder-controlled combinations face bespoke governance demands (Tesla–SpaceX). Turkish companies considering U.S. acquisitions in Q4 should build antitrust, CFIUS, and political-engagement strategy into deal timelines from day one.

This publication is for general informational purposes only and does not constitute legal advice.