David v. Park
103 Mass. 501
Mass.
1870
Check Treatment
Gray, J.

Neither of the grounds assigned by the learned judge who presided at the trial, for the ruling under which a verdict was returned for the defendant in each of these cases, is tenable.

1. The evidence introduced tended to show that the defendant falsely and fraudulently stated, as of his own knowledge, and not as matter of opinion, in the one case, that he had the inter *503est in the patent right which he undertook to sell, and in the other, that the invention was not covered by any other patent. A distinct statement of such a fact by a seller, knowing it to be false, and with intent to deceive the buyer, and on which the buyer acts to his own injury, will sustain an action of deceit, even if the buyer might have discovered the fraud by searching the records of the patent office. Brown v. Castles, 11 Cush. 348. Manning v. Albee, 11 Allen, 520; S. C. 14 Allen, 7. Watson v. Atwood, 25 Conn. 313.

2. Questions of the existence, validity or construction of letters patent for inventions, when arising collaterally in a suit in a state court, must be there tried and determined. Nash v. Lull, 102 Mass. 60. Exceptions sustained