Electronic Media reported well-placed sources said Messrs. Tisch and Frank have discussed such a move in general terms, although decisions are far from being made.
It has become clear in recent weeks Mr. Tisch is struggling to command a premium of $80 per share for CBS in the face of declining ratings and revenues.
If Mr. Frank can be persuaded to join CBS, Mr. Tisch could wait several years to realize greater return on a rebuilt network that could have more substantial value to new-media players.
Several weeks ago, Messrs. Tisch and Frank met in New York to discuss many things, including the possibility of Mr. Frank coming to CBS. Neither could be reached for comment at press time.
However, well-placed sources said Mr. Frank would only consider such an arrangement in exchange for a sizable equity stake in CBS.
"Although it would take him several years to turn things around, just Rich moving to CBS, if it happens, would immediately stir new excitement and energy at the network," said one high-level industry executive.
In the wake of the recent departure of longtime CBS Broadcast Group President Howard Stringer, "CBS needs a creative driver," a prominent Wall Street investor said.
"It could either be Rich Frank or Barry Diller, depending on how things go. The media mating game is more complicated these days, so it takes longer to work these things out," the investor said.
Mr. Frank, who doesn't leave Disney until April 24, has only begun exploring his options, which could include making his own investor-backed bid to acquire CBS, sources said.
However, events last week suggested that CBS's sale talks with prospective buyers-such as Turner Broadcasting System, TCI, Disney, Barry Diller and Viacom-have slowed.
TCI acknowledged it was, for now, ceasing discussions with Time Warner to acquire its 19.4% interest in TBS, in which TCI already owns 22%.
Industry sources say TCI's announcement signaled TCI and TBS aren't close to sealing a CBS deal.
TCI's announcement also opened the bidding for Time Warner's TBS stake to other interested parties, which could include NBC owner General Electric Co. or telephone companies such as Bell Atlantic or Nynex Corp.
Sources close to the situation said TCI, which had offered Time Warner mostly cash and some interest-bearing notes totaling about $27 a share, could simply wait out Time Warner's negotiations with other parties.
Although the negotiations had periodically included the potential swap of some TBS assets, sources close to the situation say that option is now less likely.
TBS also had asked Time Warner to agree to carry all its program services on its cable systems just in case Time Warner launches competing program networks of its own, sources said.
Acquiring Time Warner's TBS stake would make the most sense for TCI because it would give it a controlling 40-plus percent interest in the company.
TCI also is the only prospective buyer of the TBS stake who qualifies to absorb Time Warner's three TBS board seats and veto power over major investments.
Ms. Mermigas is financial editor for Electronic Media.