Some interior design firms posted ads on line to hire senior designers, but actually hiring someone was their last intentions. Instead, they just wanted to see the senior designers’ portfolios so they could possibly borrow some of the design ideas. Constantly monitoring the companies’ websites and see if any of your idea was used without your knowledge should be the key. Also, don’t email your portfolios to these kinds of design companies before a face-to-face interview will also be essential. If you have encountered the similar situation, please contact me as soon as possible.