Cressler v. Custer

Citations

• 1 MacA. Pat. Cas. 216
• 6 F. Cas. 806

Syllabus

<p>Competency of witness — interest in tiie suit. — When a question is raised as to the competency of a witness on the ground of interest, the usual test is to consider whether the witness will be affected by the event of the suit; that is, whether he has an interest, legal or equitable, (if real,) which will be secured or continued to him in the event of success, or lost '■ in the event of the defeat, of the party in whose favor he is called as a witness.</p> <p>Sm — testimony of assignee or licensee inadmissible. — An assignee or licensee has an interest in the issuance of a patent to his assignor or licensor as against a rival claimant.</p> <p>Implied license sufficient to exclude witness. — Where a person took an assignment under an impression that a certain improvement upon the original invention was included in the patent, and he used such improvement with the consent and permission of the patentee: Held, That he had an implied license from the patentee to continue the use of said improvement, which ivould discontinue upon the issuance of a patent to another inventor, and that lie was an incompetent witness for his licensor in an interference proceeding.</p>