A Micron Technology board member just sent a confident signal about the high-flying memory stock.

Often corporate insiders buy stock on the decline, scooping up shares they view as cheap and sending a message to investors that they're willing to bet their own money on a rebound.

But it's notable that Mark Liu, a former Taiwan Semiconductor Manufacturing $(TSM)$ executive who sits on Micron's $(MU)$ board of directors, did something different, buying up shares of the memory-chip maker when they've essentially never been hotter. The move suggests he thinks there's more room for shares to ride higher.

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Liu just disclosed the purchase of 23,200 shares, with his buying taking place on Tuesday and Wednesday, two sessions in which Micron's stock saw mild declines. His open-market purchases, revealed through a Thursday filing with the Securities and Exchange Commission, amounted to about $7.8 million worth of stock.

He now has direct ownership of 25,910 Micron shares that are worth about $8.7 million based on Thursday's closing price of $336.63, which sits just shy of Monday's record finish of $345.87.

While corporate insiders may opt to sell stock for a number of reasons, their buying actions are typically seen as strong signs of conviction in a company's story. That's especially true when the insider, as is the case with Liu, has deep industry knowledge. He spent more than three decades at TSMC, including as co-CEO and as executive chairman. Now he's the chairman of J&M Copper Beech Ventures, a multi-strategy investment fund, according to his biography on Micron's corporate site.

Micron didn't immediately respond to a request for comment on behalf of the company or Liu.

The stock rose 4% in premarket.

Shares of Micron have been on a blistering run, rising 75% in the last three months alone and surging 226% over the past year. Artificial intelligence has driven up the need for memory chips, and with demand well in excess of supply, Micron has been able to dramatically boost prices for both dynamic random-access memory and NAND flash memory. Some analysts are hopeful that the trend portends long-term structural changes to the memory market, which has long been cyclical.

Even with the big recent rally and a rise in earnings expectations, Micron's stock remains among the cheapest in the S&P 500.