Millipore Corporation — commonly "Millipore" — was a US life-sciences tools company founded in 1954 (originally as Millipore Filter Company, spun out of membrane-filter technology developed for the U.S. Army) and headquartered in Billerica, Massachusetts. It was publicly traded on NYSE under ticker MIL and was an S&P 500 constituent. At the time of its 2010 acquisition by Germany's Merck KGaA (a deal valued at roughly $7.2 billion, or $107 per share), Millipore reported about $1.7 billion in FY2009 sales and roughly 6,000 employees in more than 30 countries. It is no longer independent: Merck KGaA folded it into EMD Millipore / Merck Millipore, and after Merck's 2015 Sigma-Aldrich acquisition the life-science business operates as MilliporeSigma.
Products and operations. Millipore made filtration and separation membranes and devices, laboratory water-purification systems, chromatography and sample-preparation products, reagents, antibodies and kits, and bioprocess filtration consumables for pharmaceutical and biopharmaceutical manufacturing. It was organized into two divisions, Bioscience (research tools and lab products) and Bioprocess (manufacturing-scale filtration and purification), serving pharma, biotech and academic customers.
Litigation posture. The case data show one tracked matter, with Millipore as plaintiff and zero as defendant. This is an operating-company profile, not an NPE: Millipore sold real products and its single recorded suit was a defensive declaratory-judgment action, not an assertion campaign. The "plaintiff" label reflects that procedural posture rather than offensive patent enforcement.
Notable case. Millipore Corp. et al. v. University Patents, Inc., filed August 29, 1986 in the U.S. District Court for the District of Delaware. Millipore sought a declaratory judgment against University Patents, Inc. (UPI) amid UPI/ABIO litigation in California over instruments for amino-acid analysis; Millipore filed pre-emptively after acquiring German specialty-chemical maker Biosyntech GmbH. The court's 1987 ruling (682 F. Supp. 227) addressed subject-matter jurisdiction over the declaratory-judgment claim. Venue was Delaware, Millipore's incorporation state — not a plaintiff-friendly patent venue in the Eastern District of Texas sense.
Sources: Merck KGaA/Millipore transaction press releases (2010); NYT DealBook; Wikipedia (Merck Millipore); CourtListener opinion text.