Bidsquare: Fine Art, Decorative Arts and Modern Design Online Auctions The leading auction platform for online art and antique auctions from the best auction houses, auctioneers, galleries and dealers. Bid on authentic Fine Art, Antiques, Decorative Arts, Furniture, Modern Design, Asian and Chinese Antiques, Collectibles, and Fine Jewelry. Bidsquare is the premier online auction platform for leading auction houses, galleries and dealers.