Wow! Stuff said its lawyers had begun proceedings against 16 companies in the UK and European Union.
The European distribution and manufacturing rights to the remote-controlled helium filled toys are owned by Wow! Stuff, whose founders include Fife-born Kenny McAndrew and Graeme Taylor from Aberdeen.
More than 500,000 Air Swimmers have been sold since January last year when they were launched by the William Mark Corporation.
Wow! Stuff's lawyer Lincoln IP has secured two UK patents, a European Community trademark and multiple registered European Community designs for the products.