Warren Buffett’s reluctance to spend his $128 billion cash pile could be saying something about the stock market’s overall valuation.

Berkshire made a $140-a-share bid for the distributor of technology products that was topped by a $145 offer from Apollo Global Management Inc., according to CNBC.com.

The offer was another effort by the billionaire investor to put a chunk of his record $128 billion cash pile to use and signals that while Buffett is still on the prowl, he may not be willing to outbid private equity firms flush with money, Bloomberg explained.

Buffett has been stymied on the acquisition front in recent years, causing the billionaire investor to express frustration about the “sky-high” prices for decent businesses. He said earlier this year that he was working on a large deal in the fourth quarter of 2018 but it eventually fell through. The lack of deals has also pressured Buffett’s ability to maintain the stock returns that helped make him famous. Berkshire’s stock is on track for its worst underperformance since 2009.

Berkshire’s interest forced Apollo to raise its bid to one that values Tech Data at about $6 billion, including debt. Tech Data helps bring products to market for firms such as Microsoft Corp. and Apple Inc., which is Berkshire’s largest public stock investment as it has a roughly $56 billion stake in the iPhone maker.

“Prices are sky-high for businesses possessing decent long-term prospects,” Buffett said in the most recent annual letter. The Oracle of Omaha has said the premium for buying companies outright has gotten too rich for his liking partly due to competition from private-equity companies, CNBC.com explained. “We continue, nevertheless, to hope for an elephant-sized acquisition,” Buffett said in his annual shareholder letter released earlier this year.

For Berkshire, the Tech Data saga likely ends here. Buffett isn’t planning to make a higher bid, according to CNBC. His appetite for a large buyout may continue.

“He’s just not going to throw the money out and earn a rate of return below what his minimum target is,” David Kass, a professor of finance at the University of Maryland’s Robert H. Smith School of Business, told Bloomberg. “He is Buffett because he’s patient.”

Meanwhile, the data support lofty market values.

The forward price-to-earnings ratio for the S&P 500 has climbed to levels last seen around December’s sell-off, CNBC said.

The S&P 500 is also trading at about 2.14 times sales estimates for the next 12 months.

The last time the market reached such a high price-sales multiple was in September 2018 when a big sell-off began and in the first quarter of 2000 just before the tech bubble burst.

“U.S. equities remain highly overvalued relative to non-U.S. equities,” Lori Calvasina, head of U.S. equity strategy at RBC, said in a note Wednesday. “We aren’t looking for much multiple expansion in 2020.”

The biggest private-equity firms are on a tear. Apollo’s Leon Black said earlier this month that the firm is on track to almost double its assets under management to $600 billion in five years. Apollo’s higher bid, announced Wednesday after the market closed, sent shares of Tech Data surging 12% to close at $144.89 Friday in New York trading.

Tech Data, which was using Bank of America Corp. as its financial adviser, was engaged in a “go-shop” process. Buffett has typically avoided auctions where sellers seek the most money they can get, calling them a waste of time and a situation where he can’t win.

A Tech Data buyout by Berkshire would have pushed the Omaha, Nebraska-based conglomerate further into the technology realm, an area that Buffett avoided for decades. It also would have added another family-built business to Berkshire’s mix of retailers, insurers and energy companies. Edward Raymund founded the company and his son Steven Raymund ran the firm for about two decades before becoming chairman. Steven Raymund stepped down in 2017.

A potential acquisition by Berkshire would have just been a drop in the bucket for Buffett’s firm. The transaction value of $6 billion is just 4.7% of Buffett’s total cash pile.

This report uses material from Bloomberg and Reuters.