All three major US stock indexes were down in late-morning trading Monday, as investors parse ongoing developments in peace talks between the US and Iran.

Iran has offered to reopen the Strait of Hormuz in exchange for an end to the US' blockade of the country and an end to the war, media outlets reported Monday, citing officials.

In company news, Microsoft (MSFT) and OpenAI said Monday they have amended their agreement so that Microsoft will no longer pay a revenue share to OpenAI, and its license will now be non-exclusive. Microsoft will remain OpenAI's primary cloud partner, and its Azure will receive the first shipments of OpenAI products, unless Microsoft cannot and chooses not to support the necessary capabilities, the companies said. Separately, industry checks indicate that OpenAI is working with Qualcomm (QCOM) and MediaTek to develop smartphone processors, a TF International Securities analyst said. Microsoft shares were down 0.7% around midday, while Qualcomm shares were down 0.2%.

ARC Resources said Monday it has entered into a definitive agreement to be acquired by Shell (SHEL) in a cash-and-share deal valued at about 22 billion Canadian dollars ($16.17 billion). Under the terms of the deal, ARC shareholders will receive 0.40247 of a Shell share and CA$8.20 in cash consideration in exchange for each ARC share they own, representing a total consideration of CA$32.80 per ARC share. The deal is expected to close in H2, ARC said. Shell shares were down 1.3%.

Meta Platforms' (META) $2 billion acquisition of AI startup Manus was blocked by China's National Development and Reform Commission, media outlets reported Monday, citing the Chinese regulator. Meta shares were down 0.1%.

Eli Lilly (LLY) said Monday it has agreed to acquire Ajax Therapeutics for up to $2.3 billion in cash. The deal includes an upfront payment and subsequent payouts based on the achievement of certain clinical and regulatory milestones, the company said. Eli Lilly shares were down 0.5%.

Verizon Communications (VZ) reported Q1 adjusted earnings Monday of $1.28 per diluted share, up from $1.19 a year earlier and above the FactSet consensus analyst estimate of $1.21. First-quarter operating revenue was $34.44 billion, up from $33.49 billion a year ago but below the FactSet consensus of $34.82 billion. For 2026, the company said it expects adjusted EPS of $4.95 to $4.99, above the FactSet consensus of $4.90. Verizon shares were up 3.6%.

Price: 422.11, Change: -2.49, Percent Change: -0.59