Under Armour's Class C common stock surged nearly 9 percent Monday, closing at $26.29 a share.
The spike followed the company's announcement that it will change the ticker symbols of its Class A and Class C common stocks. Under Armour's Class A common stock will change to "UAA" from "UA," effective at the start of trading on December 7. On that day, the company's Class C common stock will also change to "UA" from "UA.C."
Under Armour's Class A shares gained nearly 2 percent, ending the session at $31.17.
Analyst Jim Duffy of Stifel Nicolaus said in a note Monday that Under Armour's objective behind renaming the tickers is to drive the two share class prices toward parity. Class C shares have under-performed since its creation on April 7, 2016. They do not include voting rights and are used for employee compensation, Duffy noted. He maintained a $28 target price on the stock.
"We appreciate Under Armour's execution to date and pathways for future revenue growth," he said. "With increasing fixed costs driven in part by elevated endorsement commitments, we believe the company's top line growth prospects are balanced against risk of margin pressure if growth slows."
—CNBC's Gina Francolla contributed to this report.