Carmichael Lynch, one of the largest creative agencies in the Twin Cities, is expanding through a merger orchestrated by its parent company, publicly traded Interpublic Group.

Tierney, a 100-person marketing communications firm based Philadelphia, will become part of Carmichael Lynch effective May 1, the companies recently announced. Tierney also has offices in Harrisburg, Pa., and New York City. It has been lead agency for companies like Chicago-based McDonald's and Philadelphia-based Comcast.

Carmichael Lynch will maintain its headquarters in downtown Minneapolis under chief executive Marcus Fischer with Tracey Santilli, president of Tierney, continuing in that role.

The combined company brings Carmichael Lynch's workforce to 375, Fischer said.

"With Tracy and the Philadelphia team joining us, we are expanding our creatively driven, integrated work to ensure that all of our clients benefit from this new opportunity," Fischer said.

The merger comes at an inflection point in the advertising industry as larger companies bolster their services and products to handle demand and opportunities within digital marketing. Carmichael Lynch, known for making ad campaigns, also has a public relations business and media-buying business managing more than $400 million in ad space on television, radio, websites and streaming platforms.

Carmichael Lynch, which was founded in 1962, has grown its head count over the years to add workers in those specialized units, including consumer behavior data analytics, but who can also offer diverse perspectives, Fischer previously said.

"The combination of our creative work and agency cultures ensures more innovation and an environment where this collaboration will thrive for our clients," Santilli said in a statement.

Parent company Interpublic Group, based in New York, reported revenue of $10.8 billion in 2023, down slightly from $10.9 billion in 2022. Interpublic acquired Tierney's parent company, True North, in 2001.