Infringement Analysis: 21 Defenses to a Patent Infringement Lawsuit

Copyright 2000-2011. Frederic M. Douglas. All Rights Reserved.

Determining whether a patent is infringed should entail the same process that a court would use. Generally, a court would make findings on validity, infringement, and enforceability. Below is a list of twenty-one specific defenses to patent infringement claims:

(1) Expired Patent,

(2) Noninfringement under 35 USC § 271,

(3) Anticipation by prior art under 35 USC § 102 (a), (b), (d), (e), or (g) (Subsection (g) repealed with America Invents Act),

(4) Obvious over prior art under 35 USC § 103,

(5) Double patenting,

(6) Improper inventorship under 35 USC § 102 (f),

(7) Improper scope of claims under 35 USC § 112,

(8) Fraud,

(9) Antitrust violation,

(10) Plaintiff does not own the patent (standing),

(11) License to the patent,

(12) Abandonment under 35 USC § 102 (c),

(13) Misuse,

(14) Laches,

(15) Intervening Rights,

(16) Lack of utility under 35 USC § 101,

(17) Inoperable invention under 35 USC § 112,

(18) Not statutory subject matter under 35 USC § 101,

(19) Foreign filing after non-publication request.

(20) Dis-joinder (Multiple defendants with no joint infringement).

(21) Prior commercial use – 35 U.S.C. Section 273.

I identified the above 21 defenses to patent infringement.

Note: Best Mode repealed by America Invents Act.

Do you know of any others?  Did I get any wrong?  Let me know