The studio is valued at more than 750 million euros, according to the offer.
Rovio said in a stock exchange release that it is currently not engaged in negotiations with Playtika. It said the board of directors is looking at the indicative offer to determine whether or not to proceed with it and how.
The release reminds that the indicative proposal will be subject to a number of preconditions, including satisfactory completion of due diligence, final approval by the board of Playtika, a unanimous and unqualified recommendation from the board of Rovio, and entry into a combination agreement between Rovio and Playtika.
The studio's shares went up by 38 per cent on Friday.
The non-binding offer marks the second attempt to acquire Rovio by Playtika. According to Helsingin Sanomat, the Israel-based company made an undisclosed offer for the entertainment studio in November 2022, worth 8.50 euros per share.
Playtika has made a number of acquisitions in recent years as it has tried to expand its offering beyond casino games, according to the newspaper. Reworks, the studio behind Redecor, was acquired in 2019 for an undisclosed price and Reworks, the developer of Best Fiends, for around 340 million euros in 2021.
The fourth largest studio in Finland in 2020 was shut down less than three years after the acquisition, leading to the sacking of 124 employees in Helsinki in 2022.