The series total was £317m (inc premium) which was well in advance of the £219.5m at the equivalent series last year, although marginally shy of the £329m posted at the February sales in this category.
Sotheby's secured the lion's share of top consignments, including the top lot of the series, Gustav Klimt's (1862-1918) Portrait of Gertrud Loew from 1902, which took £22m at their evening sale on June 24.
Its consignment followed a settlement between the heirs of the painting's subject and the Klimt Foundation, in whose keeping the work had been prior to restitution last year. The 4ft 11in x 17¾in (1.5m x 45cm) signed oil on canvas had been lost when the Nazis took possession of the Felsovanyi family home in Vienna in 1939.
Estimated at £12m-18m, it was one of the few Klimt works to have appeared on the market since four major oils sold at Christie's New York in 2006 after restoration to the heirs of another of the artist's models, Adele Bloch-Bauer.
A prolonged competition between two determined bidders on the night meant that the lot took over ten minutes to sell. The hammer finally came down to a round of applause.
The first restituted painting consigned for sale from Cornelius Gurlitt's hoard of art also attracted serious attention at the sale. The heir of its original owner, the Breslau industrialist and art collector David Friedmann, took back Max Liebermann's Zwei Reiter am Strand nach links (Two Riders on a Beach) in May and Sotheby's offered it here with an estimate of £350,000-550,000.
Five bidders chased the 2ft 4in x 3ft (71 x 90cm) oil on canvas before it sold to an anonymous buyer on the phone at £1.55m.
A third restored work at Sotheby's was Kazimir Malevich's (1879-1935) Suprematism, 18th Construction, consigned by the artist's heirs who had negotiated a restitution settlement with the Stedelijk Museum in Amsterdam. Estimated at £20m-30m, the 1915 square oil on canvas was the subject of a third-party guarantee and sold at £19m to a phone buyer, assumed to be the guarantor.
The overall total on the night was £178.6m (including premium), the second highest for an auction at Sotheby's London. Sotheby's February sale in this category took £186.5m.
Monet at Christie's
Christie's sale the night before made £71.5m (including premium). With fewer stellar lots, the sale was led by Claude Monet's (1840-1926) Iris Mauves as two phone bidders battled it out over the £6m-9m estimate until the hammer fell at £9.6m. From 1914-17, the picture had sold to the European vendor at Christie's New York in May 1997 for $3.5m (£2.16m) hammer. Here bidding came from a Russian underbidder on the phone, but it sold to an anonymous phone buyer.
The selling rate at Christie's matched their rivals' evening sale, with 42 of the 50 lots (84%) finding buyers.
The buyer's premium at both Sotheby's and Christie's was 25/20/12%.