The emergence of Usmanov, who spent six years in jail in the Soviet Union during the 1980s for fraud and unjust enrichment, has warmed Kroenke's relationship with the Arsenal board, though not to the point where Kroenke has joined the lockout agreement.

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In the US a retired woman sued banks in a class action suit claiming unjust enrichment under the tenets that it made payments far more expensive than they should have been.

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The money he earned from those deliveries is unjust enrichment but the core of the case is his failure to pay his bill, a breach of contract.

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He says the husband could be liable for "unjust enrichment" and forced to pay the money back.

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Other potential claims such as unjust enrichment could be rendered moot if the publishers agree to issue refunds.

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They are ready for copyright to go, seeing it as an unnecessary hindrance on the movement of information or, more simply, as unjust enrichment of large record and movie studios.

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The alleged causes of actions include breach of fiduciary duty, unjust enrichment, unfair competition, excessive executive compensation and self-dealing transactions.

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The complaint also charges Isikoff engaged in fraud, negligent misrepresentation, unjust enrichment and intentional infliction of emotional distress.

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The suit, led by writer and labor activist Jonathan Tasini, hangs on a claim of unjust enrichment.

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