Best Buy Co. founder Richard Schulze is still exploring a buyout offer for the company and is likely to seek a 30-day extension to conduct due diligence, according to two people with knowledge of the matter.

Potential private-equity investors have become more concerned about participating in a deal as Best Buy’s stock price drops, said the people, who asked not to be identified because the matter is private. Best Buy’s board may be more likely to back an offer from Schulze after recent earnings reports, one person said.

Best Buy gave Schulze a 60-day period to examine the company’s financial information. That is set to expire in the coming days, two people said.

Matt Furman, a Best Buy spokesman, declined to comment.