Cox Communications President Pat Esser threw cold water on a report saying the No. 3 U.S. cable operator has held talks over merging with Charter Communications (CHTR), according to a person familiar with the matter.  Esser is said to have told employees in an internal memo he has had no conversations with Charter or a key shareholder over a potential tie-up.

“While our standard policy is to not comment in the press on rumors related to mergers and acquisitions, the media continues to persist with these rumors and I felt it important to let you know that they are just that — rumors and speculation,” Esser wrote, according to the person who received the memo.

The Atlanta Journal-Constitution was first to report news of the memo. Spokespeople for privately-held Cox and Charter both declined to comment on the matter. 

Esser also said in the memo he has not held conversations with Liberty Media, which owns a roughly 27% stake in Charter.

Bloomberg News reported on Friday, citing unnamed sources, that Esser had discussions with Liberty over a potential deal. The report said the two companies had not had direct negotiations and that the structure of the deal hadn’t been determined.

Charter shares climbed nearly 5% on Friday on the back of the report, but fell more than 2% in afternoon trading on Monday.

Follow Adam Samson on Twitter @adamsamson.