U.S. prosecutors unsealed an indictment in mid‑March 2026 accusing three men — including Super Micro Computer co‑founder Yih‑Shyan “Wally” Liaw — of conspiring to divert about $2.5 billion worth of high‑performance servers containing Nvidia GPUs to China in violation of U.S. export controls. Authorities say the scheme routed U.S.‑assembled systems through a Southeast Asian middleman, used forged documents and removed serial numbers and labels to conceal shipments; prosecutors allege at least $510 million was diverted between April and May 2025 alone. Liaw and a contractor, Ting‑Wei Sun, were arrested; a Taiwan‑based sales manager, Ruei‑Tsang Chang, is a fugitive. Super Micro itself was not charged; the company said it is cooperating, placed implicated employees on leave, terminated the contractor, and accepted Liaw’s board resignation. Management named DeAnna Luna acting chief compliance officer. Markets reacted violently: Super Micro shares plunged roughly 33% in a single session, spurring volatile trading, analyst downgrades and multiple securities‑fraud and class‑action inquiries. The episode has prompted fresh scrutiny of export‑control compliance across AI supply chains and triggered broader investor concern about governance at key AI‑infrastructure suppliers.

Multiple plaintiff firms on March 23–24, 2026 announced investigations or securities class actions targeting a broad swathe of public companies, signalling elevated litigation risk across sectors. Portnoy Law Firm, Rosen Law Firm, Robbins LLP, Bernstein Liebhard and others issued notices or filed complaints concerning companies including Driven Brands, Masonite, Oracle, Inovio, BlackRock TCP Capital, Plug Power, Ultragenyx, Mereo BioPharma, Soleno Therapeutics, Nektar Therapeutics, Alight, PayPal, uniQure and several smaller issuers. Allegations span accounting restatements and misstated net asset values, undisclosed takeover offers, failed or misstated clinical trials, misleading partnership claims, overstated funding prospects and securities pump‑and‑dump schemes. Several notices cite sharp share price drops following corrective disclosures; many set lead‑plaintiff deadlines in April–May 2026. Firms are soliciting investors to join class actions or serve as lead plaintiffs and are positioning to seek damages and settlements. The wave includes both U.S. and foreign‑listed companies but is being driven by U.S. plaintiff firms and SEC‑reporting events.

Mastercard has agreed to acquire London-based stablecoin infrastructure provider BVNK for up to $1.8 billion, including $300 million in contingent performance payments, the companies said. BVNK, founded in 2021, offers a B2B platform that bridges fiat rails and major blockchain networks, supporting payments in more than 130 countries and processing roughly $30 billion over the past year. The price represents a substantial premium to BVNK’s roughly $750 million valuation at its December 2024 Series B. Mastercard said the acquisition will enable banks, fintechs and merchants to route cross-border remittances, business payments and payouts via stablecoins and tokenised deposits while connecting on‑chain settlement to existing corporate treasury and payments systems. The deal — the largest stablecoin-focused acquisition to date and following earlier takeover talks between BVNK and Coinbase — is expected to close by year‑end, subject to regulatory approvals and customary closing conditions. Mastercard and BVNK cited expanded geographic reach, licensing and client relationships as key strategic benefits.

Major institutional investors reshuffled holdings in US healthcare names in filings and investor letters published March 24, 2026. Brown Advisory highlighted Cardinal Health (CAH) as a top contributor in its Brown Advisory Mid‑Cap Growth Strategy Q4 2025 letter, citing improved specialty pharma mix, demand in nuclear and home health, margin recovery in medical and upside from the Solaris acquisition; CAH closed $206.40 on March 23, 2026 and has a market value near $48.5 billion. SG Americas Securities dramatically increased its Cardinal stake, acquiring roughly 708,995 shares in Q4 to total about 727,511 shares (~$149.5 million). At the same time, several Invesco funds modestly trimmed positions across providers — INVESCO S&P 500 Index Fund sold small stakes in Molina Healthcare, HCA Healthcare and Universal Health Services while reducing Cardinal by 338 shares — but boosted UnitedHealth (UNH) across multiple Invesco funds (S&P 500, Equity & Income and Growth & Income funds added shares, bringing holdings to tens or hundreds of thousands of shares valued in the tens of millions). Other managers (Seilern, E. Ohman, Clear Trail) also adjusted UNH and related positions, reflecting broad rebalancing within the sector.

A wave of fourth‑quarter 13F disclosures published March 23, 2026 shows active repositioning by several US institutional investors. TABR Capital Management LLC reported new stakes across a diversified basket including Cisco Systems ($10.13m; ~3.9% of TABR’s portfolio), Corning ($8.71m; ~3.4%), Abbott Laboratories ($7.36m; ~2.9%), Kinder Morgan ($6.48m; ~2.5%), MetLife ($5.92m; ~2.3%), Automatic Data Processing ($4.55m; ~1.8%) and McDonald’s ($3.38m; ~1.3%). Gradient Investments LLC and other managers also disclosed sizeable moves: Gradient raised positions in Coca‑Cola, ASML and ConocoPhillips while trimming stakes in Morgan Stanley and Goldman Sachs. Marshall Financial Group and Goodman Financial made selective buys and trims — Marshall added Amgen and Federal Realty, Goodman bought IBM and trimmed Affiliated Managers Group. Filings note heavy institutional ownership across many names and scattered insider selling disclosed in several companies’ SEC filings. The disclosures reflect broad sector rotation into technology, industrials, energy, healthcare and consumer staples during the quarter.