Anthropic considers letting shareholders sell in IPO, reports The Information

• Anthropic has been working on a plan to let existing shareholders sell some stock in its blockbuster initial public offering while also considering longer-than-usual lockup periods for sales after it’s public, people familiar with the process said.
• Plans to publicly unveil its prospectus after Labor day.

Secondary components in large private-company IPOs have become the standard structure for late-stage listings where employees and early investors carry years of illiquid paper; the split worth drawing is between primary proceeds to the issuer, which fund operations, and secondary sales, which are pure liquidity for insiders and can read as either orderly de-risking or a signal on insider conviction depending on size. Pairing the secondary with extended lockups is the classic compromise: it satisfies holders who need an exit at listing while limiting the post-IPO float overhang, and in past episodes of this kind the lockup expiry dates themselves have become the scheduled supply events that the stock trades around. The sequencing matters: the prospectus filing after Labor Day is the point at which the offer structure, the primary-secondary mix, financials, and the lockup calendar become verifiable rather than sourced. Until then the reporting carries the usual caveat that IPO plans of this size are reworked repeatedly before pricing. Follow-ons are the filing itself, the indicated range, and whether cornerstone or anchor demand is disclosed, since that has tended to set the tone for first-day trading in comparable mega-listings.