03/08/2012 09:41 am ET

Adam Lambert Lawsuit Reveals Singer's Worth In Russia

Adam Lambert would NEVER perform in Russia for less than $500,000 -- this according to a new lawsuit, in which a promotional company claims it was conned into thinking it could book him for a fraction of that price.

UK-based Madison Universal filed the lawsuit against a talent agency in Santa Monica named Family Productions -- claiming FP promised to broker a deal in which Adam would perform two concerts for $80,000 ... one in Ukraine and one in Russia.

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