PATENT MARKING
There are certain steps that a patent owner must take to enjoy the full benefits of the patent. First, the patent laws require that a patented article (or its container) be marked with the word “patent” or the abbreviation “pat.”, together with the patent number.[1] Failure to mark the patented product with the patent number may prevent the patent owner from recovering damages from an infringer until the infringer receives actual notice of the infringement, even if the infringer actually knew about the patent.[2] For this reason, proper patent marking is very important, and every effort should be made to begin marking as soon as the patent issues. It is also important that any licensees be required to mark the licensed product with the patent number.
ENFORCEMENT
Second, the patent owner must vigilantly enforce the patent, or risk losing the ability to do so. Laches and estoppel are two defenses to infringement. Laches arises from an unjustified delay in enforcing the patent against a known infringer. If laches is shown, the patent owner will not be allowed to recover damages for infringements occurring before suit was finally brought, although the patent owner is generally still entitled to an injunction against further infringement. As a general rule, if an infringement suit is brought within the six-year statutory limitation on damages[3] the burden is on the infringer to establish the grounds for the laches defense. On the other hand, if suit is brought after the six-year limitation period, the burden is generally on the patent owner to justify the delay.
Estoppel is a more serious defense because it may prevent enforcement of the patent. Estoppel usually arises where there is some affirmative action on the part of the patentee, such as a charge of infringement, followed by a long period of inaction during which the accused infringer relies upon the patent owner’s inaction. Under these circumstances, a court may conclude that it would be unjust to allow the patent owner to enforce the patent against the infringer. Thus, a patent owner must be vigilant in enforcing the patent, and promptly follow up on charges of infringement.
MAINTENANCE FEES
Third, the owner of a utility patent must pay maintenance fees after 3½, 7½, and 11½ years, or the patent will expire before the end of its twenty-year term. No maintenance fees are due on design patents.[4]
| LARGE ENTITY | SMALL ENTITY | MICRO ENTITY | |
| 3 1/2 Years | $2000 | $1000 | $500 |
| 7 1/2 Years | $3760 | $1880 | $940 |
| 11 1/2 Years | $7700 | $3850 | $1925 |
[1]25 U.S.C. §287(a): “Patentees, and persons making, offering for sale, or selling within the United States any patented article for or under them, or importing any patented article into the United States, may give notice to the public that the same is patented, either by fixing thereon the word ”patent” or the abbreviation ”pat.”, together with the number of the patent, or when, from the character of the article, this can not be done, by fixing to it, or to the package wherein one or more of them is contained, a label containing a like notice.”
[2] 35 U.S.C. §287(a): “In the event of failure so to mark, no damages shall be recovered by the patentee in any action for infringement, except on proof that the infringer was notified of the infringement and continued to infringe thereafter, in which event damages may be recovered only for infringement occurring after such notice. Filing of an action for infringement shall constitute such notice.”
[3] 35 U.S.C. §286 “Except as otherwise provided by law, no recovery shall be had for any infringement committed more than six years prior to the filing of the complaint or counterclaim for infringement in the
action.”
[4] 35 U.S.C. §41(b): “(b) The Commissioner shall charge the following fees for maintaining in force all patents
based on applications filed on or after December 12, 1980:
(1) 3 years and 6 months after grant, $900.
(2) 7 years and 6 months after grant, $2,300.
(3) 11 years and 6 months after grant, $3,800. Unless payment of the applicable
maintenance fee is received in the Patent and Trademark Office on or before the
date the fee is due or within a grace period of 6 months thereafter, the patent will
expire as of the end of such grace period. The Commissioner may require the
payment of a surcharge as a condition of accepting within such 6-month grace
period the payment of an applicable maintenance fee. No fee may be established
for maintaining a design or plant patent in force.