Nokia, after all, has rather a great deal of patents up its sleeve and has signed royalty-bearing agreements with Samsung, Apple, LG, Lenovo and even Blackberry.
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Nokia has actually submitted various patent violation complaints against Oppo regarding SEP and non-SEP patents. These patents have to do with security, interface and connectivity features. The problems are filed in European and Asian markets.
Oppo and Nokia signed a multi-year licensing agreement back in 2018 and it seems that the agreement is over. Nokia put out a main statement that Oppo has declined the deal of renewing the agreement so it had to take legal actions considering that Oppo continues to use those patents. The spokesperson for Nokia believes that there is still a more constructive method to deal with the circumstance.