在美国标准普尔 500 指数（S&P 500）四月上涨 10%后（为 2020 年以来最佳单月），市场又忧虑五月后续走势，因为自 1928 年以来五月一直是 S&P 500 的第三个最差月份之一，并促成「五月卖出、秋天再说」的传统警句。回购仍提供稳定需求，原因是回购可减少流通存量，推高每股收益，并在可能出现回撤时对冲压力。金融危机后，美国股市需求主要来自回购；虽然也有批评者认为这是修饰数字、掩盖缺乏现金最佳用途的做法。Donald Trump 在一月签署行政令，限制部分国防承包商的回购与股息。
当伊朗冲突的不确定性开始压抑华尔街时，Jefferies 的 Andrew Greenebaum 认为回购可减轻冲突对盈余估计的负向影响。以最近完成的执行资料来看，回购已偏离科技与通信服务：其在 S&P 500 市值占比超过 45%，但只占回购 38%；能源、金融、工业及材料四类周期性板块占回购美元值 44%，尽管它们在指数中仅约占四分之一。约 40% 的公司目前在「开放回购窗口」，且 Goldman Sachs 的回购交易台预计该窗口将持续到 6 月 12 日。Birinyi 的 Jeff Rubin 说，真正的撑盘买家并非个人投资者，而是企业本身。
As investors debate whether U.S. equities’ torrid rise is running out of steam, corporate support remains firm. Birinyi Associates reports Corporate America announced $665 billion in share buybacks over four months through April, the strongest year-start in U.S. history, while Apple Inc. approved a $100 billion plan on Thursday to reassure investors during leadership transition. Authorized repurchases are forecast at $1.55 trillion in 2026, above last year’s record, signaling confidence in earnings, revenue, and cash flow despite rich valuation multiples and lingering uncertainty over sustained oil-price impacts.
S&P 500 gained 10% in April, its best month since 2020, even as the market worries about a May pullback after a historically difficult month for the index. Since 1928, May has ranked the index’s third-worst month, reinforcing the “sell in May and go away” pattern. Buybacks remain a stabilizing buyer because they reduce shares outstanding, lift per-share profits, and can cushion volatility. Since the financial crisis, repurchases have been a dominant U.S. equity demand source; critics still label them cosmetic and ineffective for long-term value deployment. In January, Donald Trump also signed an executive order limiting buybacks and dividends for certain defense contractors.
As uncertainty from the Iran conflict rises, Andrew Greenebaum at Jefferies argues buybacks can soften negative earnings revisions for the broader market. The latest completed execution data show buybacks have shifted away from technology and communication services: those sectors are over 45% of S&P 500 market cap but account for only 38% of repurchases, while cyclical sectors in energy, financials, industrials, and materials account for 44% of buyback value despite about one-quarter index weight. About 40% of companies are currently in open buyback windows, which Goldman Sachs expects to stay open until June 12, supporting Jeff Rubin’s view that corporations, not retail investors, are the ultimate dip buyers.