Seagate’s shares rose 1.05 percent Friday to close at $24.96 and were up about 4 percent for the week after news that it might enter the flash memory market. There does not appear to have been any significant increase in trading of Seagate options.

With a booming economy and $1.33 trillion in foreign-exchange reserves, Chinese companies are in a position to acquire American companies, as Japanese and West European companies were several decades ago. While those earlier acquisitions were often opposed out of fears that they would damage American economic competitiveness, the acquisition of American companies by Chinese companies is regarded with more suspicion, particularly in the high-tech sector.

Since the Lenovo sale, the government has become increasingly concerned about technology security, according to members of federal advisory committees.

“Seagate would be extremely sensitive,” said an industry executive who participates in classified government advisory groups. “I do not think anyone in the U.S. wants the Chinese to have access to the controller chips for a disk drive. One never knows what the Chinese could do to instrument the drive.”

The transfer of advanced disk drive manufacturing technology would give the Chinese a major leg up in competing in information technologies. China, however, still lags in basic manufacturing skills like semiconductor design and manufacturing.

“This is clearly a critical component of a computer system and the purchase by the Chinese or other nations merits a full review to determine what our risks are,” said Michael R. Wessell, a commissioner of the U.S.-China Economic and Security Review Commission, a group that monitors the national security implications of trade with China for Congress.

I.B.M., which invented the disk drive in the 1950s and which dominated the industry through the 1990s, sold its disk drive business to the Japanese computer maker Hitachi in 2002, leaving just two American companies: Seagate, based in Scotts Valley, Calif., and Western Digital, based in Lake Forest, Calif.