Michael Geist points to a new decision from Canada's Supreme Court ruling that Lego couldn't use a claimed trademark on the interlocking shape of its blocks to insulate them from competition after its patent expired. The ruling echoes a recent U.S. Supreme Court decision, TrafFix Devices Inc. v. Marketing Displays Inc. (2001), that an expired patent couldn't be extended by a claim that the design had acquired trade dress distinctiveness.

Lego (Kirkbi) had patented the Lego system of interlocking blocks and now claimed that even after the patent expired, the "distinctive orthogonal pattern of raised studs distributed on the top of each toy-building brick" had become "LEGO indicia" due protection as an unregistered trademark. Without this protection, Kirkbi protested, Mega Blok would be able to free-ride on the popularity established by Lego's hard work and reputation for quality.

One must start from the problem the appellant faced when its patents expired. ...[T]he very cleverness and flexibility of LEGO technology, of the combination of studs on top of the brick and tubes under it, had almost turned "LEGO" into a household word. Source and product became identified. LEGO bricks, for many, came to designate these small colourful building blocks, with their clever locking system. But when the patents expired, the LEGO technology fell into the public domain. The LEGO name, whether on the product, on its packaging or in its advertising, remained protected, but the monopoly on the wares themselves was over. The monopoly had been the key to the building up and preservation of LEGO’s market share, and so Kirkbi employed a number of different means to protect it, one of which was the assertion of a trade-mark.

The court properly recognized that the patent confers a limited monopoly. In Canada, as in the United States, patent protection is temporary: "Patent protection rests on a concept of a bargain between the inventor and the public. In return for disclosure of the invention to the public, the inventor acquires for a limited time the exclusive right to exploit it." Entry into the public domain after the patent's expiration is a core part of the public-private bargain -- a bargain that can't be abrogated by trademark claims.

True, Kirkbi had built a Lego empire, but as an empire founded on the functional properties of Lego's interlocking bricks, its moats came with an expiration date. "Free riding" after that date benefits society by giving more companies the chance to build interlocking bricks, giving more kids (and non-kids) access to reasonably priced building kits.

The fact is, though, that the monopoly on the bricks is over, and MEGA BLOKS and LEGO bricks may be interchangeable in the bins of the playrooms of the nation – dragons, castles and knights may be designed with them, without any distinction. The marketing operations of Ritvik are legitimate and may not be challenged under s. 7(b) [of the Trade-marks Act].

This reasoning, like the similar U.S. TrafFix decision, reflects a general feature of Anglo-American intellectual property law: Intellectual creations generate value that is shared between the creator and the public. We do not say, "if value then right to exclude," but rather that creators accept the bargain of limited-scope rights when they create.

Let us not forget these principles in the copyfight. Though the term of copyright may never expire in our lifetimes, its scope is cabined by fair use, first sale, and limits on the activities copyright reaches. The copyright bargain authors accept when they write and publish does not include the right to charge for every search index or to break your computer in the name of "securing" music.