When drafting claims practitioners often struggle defining limiting terms such as “a,” “at least one,” and “one.” However, the key to defining these terms may be to focus less on the term itself and focus more on the context surrounding the term. For example, the context surrounding the term “one” may be drafted in such a way that “one” may mean “one and only one.” On the other hand, the context surrounding the term “one” may be drafted in such a way that “one” may mean “at least one.” As suggested in IGT v. Bally Gaming, Inc., focusing on the context may prevent unintentionally errors.
In IGT v. Bally Gaming, Inc., Bally Gaming, Inc. (Bally collectively) appealed the district court’s grant of summary judgment of infringement of certain claims of U.S. reissue patent nos. RE37,885 (’885 patent) and RE38,812 (’812 patent) owned by IGT. In particular, Bally appealed the district courts interpretation of the term “one.”
IGT accused Bally of infringing a method for rewarding slot-machine players over and above the normal device payouts when Bally offered two promotions – Power Rewards and Power Winners. IGT then filed for summary judgment of infringement. In deciding the question of summary judgment, the district court construed a number of claim terms. The court then determined that Power Winners had infringed but that Power Rewards did not. Accordingly, summary judgment of infringement was granted with regard to Power Rewards and summary judgment of non-infringement was granted with regard to Power Winners.
Bally appealed arguing that the district court erred in a number of its claim constructions and in its grant of summary judgment of infringement. IGT cross appealed arguing that the district court erred in other claim term constructions.
The CAFC reviewed the district court’s claim construction de novo. Although many claim terms were discussed in the opinion, of particular interest is the CAFC’s discussion of the term “one,” which appeared in several of the limitations of one of the asserted patents. One such example, which was relied upon by the CAFC for it’s interpretation of “one” is as follows:
issuing a command over the network to one of said preselected gaming devices responsive to a predetermined event; and
paying at said one gaming device in accordance with the command.
In its appeal, Bally argued that the meaning of “one” in the above limitations is “one and only one.” Specifically, Bally argued that the claims rely on the “one” language for antecedent basis with the requirement of “paying at said one gaming device.” According to Bally, this demonstrated that the command (and thus the payout) must only be awarded to a single player at a single device. For additional support, Bally points to the fact that other claims of the asserted patent use the terms “each” gaming device or “at least one” gaming device, thus the drafter must have intended “one” to mean one and only one device could receive a payout.
On the other hand, IGT argued that the claims do not limit the system to pay out at a single one of the preselected devices. IGT argued that the claims only require that a single command pay out at a single machine. In other words, as long as one command goes to one machine and causes that machine to payout, that command meets the claim limitation regardless of how many other commands are sent. For support, IGT points to the fact that that Bally ignores other claims of the asserted patent that recite that the command is sent to “only one” gaming device. IGT argued that this shows that the drafter knew how to claim a “one and only one” embodiment and that the word “one” should not be so limiting.
The CAFC agreed with IGT that the meaning of “one” did not mean “one and only one.” Rather, “one” meant at least one. As the CAFC explained, the meaning of the word “one” in the claim is clear from the words that surround it—“issuing a command over the network to one of said preselected gaming devices” and “paying at said one gaming device in accordance with the command.” Specifically, the use of “one” in the above limitations was limiting in that a command will go to one of the preselected gaming devices causing at least one device to pay. The term “one” modified the devices that would receive the command, not the number of commands that could be issued. The CAFC further explained that the second use of “one” further supports this construction – “one” gaming device will pay in accordance with the command. Accordingly, the term “one” is defined by the words and context that surround it.
A copy of the CAFC opinion may be found here.