Aavid Thermalloy LLC v. Cooler Master Co., Ltd., 4:17-cv-05363

Aavid Thermalloy sued Cooler Master for patent infringement involving vapor chamber cooling devices and identified four accused part numbers in its Local Patent Rule (LPR) 3-1(b) infringement contentions.
Aavid sought broad discovery: all Cooler Master "Products" defined as vapor-chamber products with one or more mounting holes (documents identifying products sold/imported since Jan 1, 2017; interrogatory for product identifiers; admission of offers to sell).
Aavid claimed it could not identify additional Cooler Master vapor-chamber products without discovery because vapor chambers in downstream products are often unmarked.
Cooler Master contended courts routinely deny discovery into products not identified in LPR 3-1(b) and that its products are commercially available and at least some are marked.
The court applied the district’s rule that discovery of unaccused products is allowed only if the plaintiff could not have discovered them absent discovery and must articulate how unknown products share the same (or substantially the same) infringing structure as accused products.
The court denied Aavid’s motion to compel, finding Aavid had not sufficiently tried to identify products pre-discovery and its requests were overbroad and not tied to the asserted claim structure.

Issue	Plaintiff's Argument	Defendant's Argument	Held
Whether Aavid may compel discovery of unaccused Cooler Master products not listed in LPR 3-1(b).	Aavid: it cannot reasonably identify all Cooler Master vapor-chamber products without discovery because chambers are often unmarked in downstream products.	Cooler Master: LPR precedent bars discovery into unaccused products; products are commercially available and some are marked.	Denied — Aavid failed to show it could not discover products absent discovery and did not make sufficient pre-discovery efforts.
Whether Aavid’s requests are appropriately tailored to alleged infringing structure.	Aavid: defined "Products" by vapor chamber with mounting holes; seeks broad product identification.	Cooler Master: requests are overbroad and not limited to products that share the asserted claim features (e.g., two bonded plates, boundary/edge lip).	Denied — requests overbroad; Aavid did not articulate how all requested products share the same or substantially the same infringing structure.

No authorities with official reporter citations were relied on in the opinion; the court principally discussed district decisions available via electronic (WL) citations regarding discovery into unaccused products and the exception when the plaintiff could not have discovered the products absent discovery.