According to the speculation, Citic Securities - China's largest brokerage - and the Korea Development Bank (KDB) have held advanced talks over the possible deal.
However, Citic has moved to pour cold water on the rumors - which originated from a report in the Financial Times.
Lehman has been one of the banks worst hit by the global credit crunch, and is expected to reveal a further $3 billion of asset writedowns at its next financial declaration in September.
The Wall Street Journal has also claimed, citing inside knowledge, that the US Federal Reserve was concerned last month at speculation that Credit Suisse was about to pull a credit line from the troubled bank.
Tan Ning, board secretary of Citic, said: "We have had no such talks as far as I know...we know there are always lots of rumors like this in the markets but we are not in formal talks with Lehman or other firms on stake investments."
KDB and Lehman have thus far declined to comment.