New York-based hedge fund Starboard Value has acquired a stake in Starbucks joining fellow activist Elliott Investment Management in investing in the troubled coffee retail chain, according to a report by The Wall Street Journal.

Starbucks stock, which has fallen by nearly 20% this year due to declining sales and a revised earnings forecast, climbed 2.6% on Monday after news of Starboard's investment broke. The size of Starboard's stake is not known at this time.

In addition to Starbucks, Starboard Value’s portfolio includes stakes in Bloomin' Brands, GoDaddy, News Corp and Salesforce, among other holdings, according to its latest 13F filing.

Elliott, which has been actively pushing for changes at Starbucks, is seeking board representation and may consider a proxy fight for a seat. It remains uncertain whether Starboard Value will pursue a similar strategy.

Former CEO Howard Schultz remains the largest individual shareholder in Starbucks, despite being replaced by Laxman Narasimhan last March.