Viacom and Snapchat have enjoyed a harmonious relationship as of late, thanks to an agreement struck earlier this year that allows the New York owner of MTV and Comedy Central  to sell U.S. advertising for the social-media darling and bundle it into packages with its TV clients.

Has their friendship become so deep that Viacom’s ad-sales chief might leave his roost and move to Snapchat as a top executive?

People familiar with the situation tried to throw cold water Tuesday on a New York Post report suggesting that Viacom ad-sales honcho Jeff Lucas would join Snapchat as its chief operating officer on July 8 – smack dab in the middle of negotiations and logistical planning for TV’s annual “upfront” market, when U.S. media companies sell the bulk of their ad inventory for the coming programming cycle. One of these people dismissed the report as speculation and said Lucas was entirely focused on Viacom’s upfront process. A person familiar with Snapchat said Lucas was not joining the vanishing-messages app company as chief operating officer.

Speculation about Lucas moving to Snapchat has been rampant for months. When the two companies unveiled their pact recently, it was disclosed that Lucas was advising Snapchat on advertising matters. As rumor has it, the executive has tried to get out of his contract with Viacom, to little avail. The Post report would suggest that has changed.

Lucas also has significant responsibilities at Viacom, where he has over he past few years built up staff that help advertisers place their commercials with more precision based on reams of consumer data; create commercials that reflect the tone and feel of the programs and networks on which they appear; and help emphasize the ads and their messages in consumer media.

Viacom’s “upfront” process is believed to be underway. As the owner of Nickelodeon, the company typically moves early, as advertisers start haggling with kids’ networks before they move to broadcast outlets and general-entertainment cable.

According to ad buyers and other people familiar with the discussions, Viacom has already renewed some multi-year agreements for Nickelodeon ads, which would eat up commercial inventory and place pressure on buyers to get deals done.  Because the current generation of kids is familiar with mobile devices and streaming video, TV ratings have been under pressure for years, though Nickelodeon and Nick. Jr. have made ratings gains in recent months, stealing share from Time Warner’s Cartoon Network, according to Todd Juenger, a media-industry analyst with Bernstein Research.

Loss of its ad-sales chief would put Viacom in a difficult spot. The company has to work harder than its rivals in many cases, owing to ratings drops at flagship networks like MTV and Comedy Central, both of which have had new leaders installed in recent months. Under Lucas, the company has kept advertising coming in, albeit with sweeteners such as reduced ad loads and moderate rates of increase in the cost of reaching 1,000 viewers, a measure known as a CPM. A move to Snapchat would add to the uncertainty surrounding the company, where the board of directors appears to be grappling for control with its controlling shareholders, the Redstone family.