OpenAI Jumps 32%, Airtable Crashes 56% as Private Market Returns Diverge - Salesforce (NYSE:CRM), SpaceX…

OpenAI rose 32.3% in September, while Airtable fell sharply by 56.1%. This shows a growing gap between the performance of private companies as investors become more careful about where they put their money and discounts on shares sold in secondary markets grow larger.

These very different results came as Forge's equally weighted Private Market Index rose 1.4% during the month. The overall increase hid large differences between individual companies. Forge's October update on private markets shows that gains are still concentrated in a few well-known businesses, while other companies face greater pressure on their valuations.

OpenAI made the largest contribution to the cap-weighted Forge Accuidity Private Market Index, which rose 3.4% in September. Defense technology company Anduril also helped the index by gaining 7.3%, while publicly traded SpaceX (NASDAQ:SPCX) rose 5%.

However, other companies lost value. Airtable had the biggest drop among the companies tracked by the index. Postman followed, falling 33.7%. Cryptocurrency exchange Kraken dropped 19.1%, while AI chip startup SambaNova Systems fell 12.4%.

Airtable's decline reflected its sale to Bending Spoons for $1.28 billion, a price lower than expected, according to Forge. Meanwhile, Fin, previously known as Intercom, rose 78.7% after Salesforce (NYSE:CRM) bought the company for $3.6 billion on September 10.

These differences show how the prices paid in acquisitions, developments at individual companies and changes in investor demand can lead to very different results across private markets.

Buyers Gain More Power in Private Markets

The uneven results come as the balance of power between buyers and sellers changes in the secondary market, where investors buy and sell existing shares in private companies.

In September, buyers' stated interest made up 43.5% of all new and updated expressions of interest on the Forge Marketplace. This was down from 45% in August and 48% in July. It was the fourth month in a row that this share fell, bringing buyer participation to its lowest level in about two years.

At the same time, the middle-priced secondary-market deal was completed at a 9% discount to the company's valuation in its most recent primary funding round. In August, that discount was 3%.

Prices also fell among the more expensive deals. In August, deals at the 90th percentile were priced 58% above the valuation from the last primary funding round. In September, that premium fell to 15%. At the 75th percentile, the premium dropped from 11% to 6%.

These changes suggest that more sellers are entering the market, giving buyers greater power to negotiate. This could create opportunities for investors to buy shares in private companies at lower prices.

However, Forge warned that monthly changes in prices may reflect differences in which companies were traded, rather than a general change in the value of the entire market.

Valuations of $20 Billion or More Remain Strong

Despite the different company returns and lower prices in secondary markets, many of the largest private companies have kept their valuations.

Of the 40 companies tracked by Forge that have reached valuations of at least $20 billion, 28, or 70%, kept their valuations at or above that level in their most recent funding round or were sold at a higher valuation.

Companies in this group include Anduril, which Forge valued at $123.8 billion; financial technology company Ramp, valued at $60 billion; and AI startup Cognition, valued at $48 billion.

According to Forge, five companies raised money at valuations of $20 billion or more between early August and the time of its report. By comparison, eight companies did so during all of 2025.

These findings suggest that weakness in private markets is not affecting every company in the same way. Some businesses still attract investment at high valuations, while others face sharp price cuts as acquisitions and secondary-market trading change what investors expect companies to be worth.

For investors, the challenge is to identify companies that can keep growing over time and separate them from companies whose earlier funding-round valuations may no longer match what buyers are willing to pay.

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