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Using Patents In Products Liability Cases

Several years ago I represented a child who received serious facial scars when he was thrown from a Yamaha Trimoto - three-wheeled all-terrain vehicle (ATV) - during a turn. Trimotos roll over unexpectedly because of their high center of gravity and their solid rear axles, which contribute to their instability because the two rear wheels drive at the same speed, rendering turning difficult. Under some conditions, the vehicle will continue forward instead of turning.

This instability could have been corrected by including a rear differential to allow the wheels on an axle to rotate at different speeds. To find evidence that Yamaha knew of the need for a differential, I conducted a patent search. A patent is the federal government's grant of a property right to an inventor. It excludes others from making, using, or selling the new design or invention for a period of time. About a year ago, the United States lengthened new invention protection to 20 years from the time the application is filed, bringing the U.S. in line with the international community. Design patents protect patentees' designs for 14 years from the time they are granted.

Patents are issued by the U.S. Patent and Trademark Office (PTO) of the Department of Commerce. To obtain a patent, an applicant must meet the five substantive requirements of 35 U.S.C. SS 101-103, 115; (1) patentable subject matter, (2) originality, (3) novelty, (4) utility, and (5) non- obviousness.

Under SS 102(B), 111-118, four procedural requirements must also be met. The inventor must file an application:

  • with the PTO;
  • within one year of public use or publication of the invention;
  • with a specification containing "a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise and exact terms as to enable any persons skilled in the art to which it pertains ... to make and use the same," and
  • with one or more claims "pointing out and distinctly claiming the subject matter which constitutes the invention and no more."
Because of these requirements, inventors generally detail all safety-related advantages in patent applications. Consequently, patents often contain admissions that can serve as critical evidence in products liability cases. Patents can prove defect, demonstrate the feasibility of alternative designs, and establish a company's knowledge of a hazard. In addition, patent information can establish state of the art engineering, provide a basis for expert opinions, and serve as the basis for questions during cross-examination. Techniques for finding patents appear on the next page.


Trimoto Case

The patent search in my Yamaha case revealed the company was assigned a differential patent for its Trimotos by an employee, James Grinde (U.S. Patent No.4,561,518). The patent provides in pertinent part:
In this prior art three-wheeled vehicle identified above (Trimoto), a problem is often encountered in cornering. That is, when it [sic] desired to round a corner, the driver must be sufficiently skilled and familiar with the use of the vehicle to lean properly toward the outside wheel. The natural tendency is for an untrained driver to lean into the turn, but such a maneuver is ineffective and actually makes turning more difficult.
The patent directly contradicted Yamaha's position that Trimotos are easy to turn and that turning techniques are intuitive for an untrained operator.

Nevertheless, Yamaha denied the differential should have been incorporated into the Trimoto design or that the subject patent was intended to apply to Trimotos. The company also denied many representations made in the patent. Yamaha and Grinde contended it applied only to utility ATVs-those operated at low speeds for work purposes, such as maintenance of golf courses.

To obtain information not publicly available in the file wrapper or the patent itself I had a subpoena duces tecum served on Yamaha's patent attorney; who was identified in the patent. Yamaha moved to quash the subpoena on the ground the information sought was protected by the attorney-client privilege. I argued the deposition was proper to discover all facts Yamaha provided regarding the patent.

I cited an infringement action, Status Time Corp. v. Sharp Elecs. Corp., 95 F.R.D. 27 (S.D.N.Y. 1982). There, a U.S. district court considered claims that correspondence and documents from a patent attorney's file were protected from disclosure by the work-product doctrine and the attorney-client privilege. The court held the documents were not work product because they were not generated in anticipation of litigation. Moreover, the Status Time court ordered an in camera inspection of the documents to determine whether the attorney-client privilege applied. The court noted that exclusively technical documents do not fall within the privilege. The court also reviewed earlier cases that held "the privilege did not apply to communications arising out of the prosecution of patent applications, for in prosecuting them, the patent attorney was not `acting as a lawyer.'" I also relied on Bio-Rad Lab., Inc. v. Pharmacia, Inc., 130 F.R.D. 116, 126 (N.D. Cal. 1990), in which the court stated:
In the field of patent litigation, it is the general rule that the attorney-client privilege does not prohibit disclosure of communications to the attorney from the client largely consisting of factual information to be used for disclosure in the patent application process because the attorney is considered "merely serving as a conduit for factual infor mation" and "not acting primarily as a lawyer".. This rule, known as the "conduit theory" of patent prosecution, extends "to any materials submitted by a client to his attorney with the intent that they be passed on to a third party or to a file. With regard to such documents, the necessary element of confidentiality is lacking."

Based on these decisions, the court ordered the deposition with production of most of the attorney's file. Included in the production was a letter responding to the PTO's initial patent denial on the ground of lack of novelty. In that letter, Yamaha argued it was novel to place a differential on a recreational ATV-directly contradicting its earlier representation that the patent was solely for utility ATV's.

With this information uncovered, my client and Yamaha agreed to settle the case-in which the child had incurred $2,300 in medical expenses-for $75,000. Landry v. Yamaha Motor Corp. USA., U.S. Dist. Ct., E.D. Wis., No. 91-C-0204, Sept. 8, 1992.

Representations made to or by a patent attorney can prove pivotal in a products liability case. When pertinent patents are located, you should routinely attempt to depose the patent attorney. Review the inventor's representations about the patent's purpose and function, and explore all oral and written communication among inventor, assignee, patent attorney, and the PTO. In this way, you may discover damaging documents or testimony that can ensure a successful outcome.

*John C. Cabaniss is a sole practioner in Milwaukee, Wisconsin.
[The parties' briefs in the Landry case on defendant's motion to quash the subpoena of its patent attorney and the trial court's order denying defendant's request are available through the Offerings section at p. 101, courtesy of Mr. Cabaniss]



Finding Patents

Every patent is assigned a unique number that is placed on the product. If you know the patent number, you can get a copy of the patent from a national depository library. To locate the nearest depository, call the PTO Public Service Center at (703) 308-HELP.

If you don't know the patent number, you can do a computer search at the depository library. Typically, employers require employee inventors to assign all rights, title, and interest in an invention to the employer. Thus, patents are often listed under the name of the defendant company.

Through a computer search, you can identify the patent by specific manufacturer, products of like classification, subclassification, or key words. The search generates a printout of patent titles and numbers from which pertinent patent abstracts can be selected for review.

You can also search for patents on the Internet. PTO databases include patents from 1976 through the present. There are three distinct search avenues, and each has easy-to-follow directions:
  • The Advanced Search Page
    http://patents.cnidr.org:4242/access/search-adv.html
  • The Boolean Search Page
    http://patents.cnidr.org:4242/access/search-bool.html
  • The Simple Search Page
    http://patents.cnidr.org:4242/access/search-simp.html

After finding a patent, obtain a certified copy of it and the related file wrapper and contents, which often contain information such as correspondence between the PTO and the applicant. You can order this information by writing to the Superintendent of Documents, U.S. Government Printing Office, Washington DC 20402, or calling (202) 512-1800.
You can also obtain a copy by contacting the Patent and Trademark Copy Sales by phone (703) 305-4350; fax (703) 305-8759; Internet e-mail ptcs@uspto.gov ; or by writing to Patent and Trademark Copy Sales, Box 9, Washington, DC 20231.

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