After years of stops and starts on the way to the altar, Viacom and CBS finally have a date for their corporate nuptials.

The companies said they expect to close the all-stock transaction after the close of trading on December 4. On the next day, December 5, the companies will become a single entity, ViacomCBS Inc., with shares trading on the Nasdaq under the new ticker symbols, VIACA and VIAC. The company will then become eligible to be included in the Nasdaq 100 index, Viacom and CBS said.

When the deal was first announced last summer, it was valued at $30 billion, but several billion dollars have been shaved off in the months since as the stocks of both companies have sagged. The market seems to still have doubts about the potential for the companies to deliver more value as one combined company, returning to the corporate configuration they were in from 2000 to 2006.

Shari Redstone, who runs CBS and Viacom controlling shareholder, National Amusements, acknowledged the doubts in an appearance this month at the Paley Center in New York. “Skepticism is very motivating,” she said.

One central question on the minds of investors is whether ViacomCBS will have adequate scale to compete — not only with the tech giants increasingly playing a central role in media but also with traditional rivals like Disney and Comcast.

“We absolutely have enough scale,” Redstone said. “People make a mistake and they look at scale as being about market cap. Scale is not about market cap. Scale is about the ability to create the quality and quantity of content that people want to see. When you look at Viacom and CBS combined together, we have an incredible library. We have incredible IP. We spend over $13 billion on content. We can compete with the best of them.”