1992 29c New York Stock Exchange Bicentennial, Center Inverted, n.h., v.f., with 2008 PSE certificate, graded "VF-XF85". (Two panes containing this invert error were discovered, for a total of 56 examples recorded. The bottom rows of each pane have the black completely missing (twelve stamps) as the vignettes for these were printed off the top of the sheet) cat. $17000 (Cat No. 2630c) (Image)

Cat. $17000, Est.US$8,500

1930 5fr+5fr green and carmine, Center shifted and Inverted, l.h., v.f., signed Brun (YT 99a, Euro 1,000) cat. $750 (Cat No. B26a) (Image)

Cat. $750, Est.US$400

1899 1p blue & black, center inverted, h.r., usual brownish gum, fresh and well centered, deep colors, signed Behr, etc., v.f., with 2008 Pascal Scheller certificate, cat. $2000 (Cat No. 139a) (Image)

Cat. $2000, Est.US$1,000

1899 5p orange and black, center inverted, l.h. (if at all), centered to top, fine and rare stamp, only 50 printed, handstamped guarantee marks, cat. $2750 (Cat No. 140a) (Image)

Cat. $2750, Est.US$1,200

1910 Centenary, 1/2c-5p inverted centers, the complete set (as issued) of seven, all but one with sheet margin, lightly hinged, couple n.h., well centered and post office fresh, v.f., signed Kneitschel,l etc., with Alberto Solari certificates. A very rare set of inverts (YT 148/59var) cat. €6300 (Cat No. 160a/173a) (Image)

Cat. €6300, Est.US$5,000

1917 San Martin, 20p blue & claret, center inverted, l.h., with 2002 Philatelic Foundation Certificate, ex-Sagar. Only 50 issued, all off centered (Kneitschel 312a "todos los ejemplares de esta hojo unica son descentrados") (YT 227a) cat. €1400 (Cat No. 246a) (Image)

Cat. €1400, Est.US$750

1919 Parliament Building, 2k vermilion and black, Center Inverted, perfectly centered with wide, even margins, beautiful color, small h.r., fresh and v.f., signed Mueller, with 1967 Friedl certificate. A rarity, especially in such beautiful condition, (ANK 284D, Euro 4,000) cat. $2750 (Cat No. 219a) (Image)

Cat. $2750, Est.US$2,500

1919 Parliament Building, 4k carmine & black, Center Inverted, l.h. (if at all), v.f. (ANK 287D, Euro 2,000) cat. $2100 (Cat No. 222a) (Image)

Cat. $2100, Est.US$1,500

1919 Parliament Building, 20kr violet gray & lilac brown, Center Inverted, neat postmark (Wien) and well centered, excellent colors, with usual irregular perforations at bottom, slightly improved at left, otherwise v.f., one of the finest of the less than 15 (!) known, with 2010 Soecknick certificate which confirms that practically all known examples of this great Austrian rarity have defective perforations (they were carelessly torn by hand) (ANK 291D, Euro 40,000) cat. $40000 (Cat No. 226a) (Image)

Cat. $40000, Est.US$15,000

1895 Stanley Falls, 10c greenish blue and black, center inverted, compound perforation 14:13 1/2, bright colors, well centered for this difficult issue, h.r., fine, signed Roger Calves, with 1998 BPA certificate (COB 18Bvar; unlisted as compound perforation) cat. €2500 (Cat No. 18a) (Image)

Cat. €2500, Est.US$1,500

1909 Portraits, 10c, 20c and 2b set of three, each with center inverted, n.h., fine-v.f. (Cat No. 79-81var) (Image)

Est.US$150

1916 Legislature Building, 10c orange & blue, Center Inverted, block of four, l.h. at left, right stamps n.h., v.f. (catalogued as hinged singles) cat. $800 (Cat No. 116c) (Image)

Cat. $800, Est.US$250

1924 10c vermilion & black, Center Inverted, l.h., fine, signed Sanabria, Irwin Heiman, etc., with Calves certificate. A rare stamp, only 50 issued, cat. $2500 (Cat No. C1a) (Image)

Cat. $2500, Est.US$1,500

1891 100r blue & red, frame inverted, four unused singles, part original gum, h.r., also two used singles, various shades and perforation varieties, mostly fine or better, ex-Cunliffe, cat. $920 (Cat No. 109a) (Image)

Cat. $920, Est.US$300

1932 Captain Cook, 1d black & lake, center inverted, canceled to order and tied on piece by Rarotonga cds, fine example of this rarity, with 2023 Royal certificate (a single pane of 80 was issued and sold at Rarotonga. One of the key inverted centers of the world and a major British Commonwealth rarity. Only five (!) used examples recorded) (SG 100a, £8,500) cat. $9500 (Cat No. 85a) (Image)

Cat. $9500, Est.US$4,000

1932 2 1/2p dark ultramarine & black, Center Inverted, n.h., fine (SG 102var) (catalogued as hinged) cat. £300 (Cat No. 87var) (Image)

Cat. £300, Est.US$150

1920 1sh bright orange & orange, Frame Inverted, h.r., slight overall toning, small surface rub at top right, really of no consequence, well centered. A v.f. example of the 1sh Statue of Queen Victoria, with frame inverted (according to most accounts this "Inverted Frame" variety was discovered by a local collector at the small Post Office in Manchioneal, a village on the coast of Jamaica in March 1922. It is presumed that only one sheet of 60 must have had the error, with half the sheet going to Manchioneal and some being fiscally used, while, more than likely, the other half sheet going to Kingston, as used copies of the error exist with Kingston cancelations. Estimates vary among specialists as to the exact number of these errors that still exist - some as low as only ten - to no more than approximately 20). An important British Commonwealth rarity, ex Cameron and Mahfood collections (SG 85a, £40,000) cat. $40000 (Cat No. 83a) (Image)

Cat. $40000, Est.US$15,000

1901 8c red and black, frame inverted, overprint reading down, oval of bars cancel as always (this rarity is only known used, canceled to order), unobtrusive cancel leaving the complete inverted center vignette untouched, beautiful fresh and unoxidized color, usual centering, fine and most desirable stamp in sound condition, less than 40 reported, with 2009 Philatelic Foundation certificate (SG D6ba,£8,500) cat. $12000 (Cat No. J6a) (Image)

Cat. $12000, Est.US$5,000

1897 7 1/2p black and green, Center Inverted, l.h. and well centered example of this popular rarity, trivial natural gum creases, v.f., with clear 1961 BPA certificate. Only 60 printed (SG 48a), cat. £7500 (Cat No. 47a) (Image)

Cat. £7500, Est.US$4,500

1911 50s ochre and black, Center Inverted, canceled Plovdiv June 13, 1913, v.f., signed Herbert Bloch, Karaivanoff and Mikulski, with their 1935 and 1985 certificates. This major error occurred as the bicolored set was printed first in one color and then passed through the press again for the second time. While a premier rarity of Bulgarian philately, this error actually went unnoticed by the public for seven years, the first example being discovered in 1918 by a Nicola Kochanov in Sofia. All of the known (only about 30) examples are used (Mi.86K, Euro 7500) cat. $4250 (Cat No. 97a) (Image)

Cat. $4250, Est.US$4,000

1916 10c blue & black, type II, Center Inverted and shifted downwards, usual centering, heavy h.r., rare (YT 113a, Euro 600) (Cat No. 131c) (Image)

Est.US$150

1924 2c-5p numerals, two of last, left sheet margin se-tenant block of 12, centers inverted, n.h., fine-v.f., with 2008 APS certificate. A scarce multiple, only a handful intact se-tenant blocks exist, (Cat No. J48-58var) (Image)

Est.US$600

1907 1c, 2c, 5c (two copies, one with center shifted to bottom), 50c, 2col and 2col Waterlow Issue, each with Center Inverted, 2c unused without gum, others h.r., minor faults (2c repaired upper left corner, 50c small thin, 5c some toned gum), otherwise fine-v.f., extremely rare "set", only a few of each exist, accompanied by a 2016 Brian Moorhouse certificate for the group, ex-Mayer collection (last offered in 2016 H.R. Harmer sale, Lot 31, $25,000 hammer) (Cat No. 59/68var) (Image)

Est.US$15,000

1907 2c yellow green and black, perf. 14, center inverted, unused with full original gum, h.r., usual imperceptible toning, bright colors and fresh, v.f., with 2008 Brian Moorhouse cert. ("less than five copies of this variety are known") (Cat No. 60a,var) (Image)

Est.US$5,000

1907 5c yellow and dull blue, perf. 14, center inverted, unused with full original gum, h.r., trivial corner crease at top right, fresh colors, v.f., with 2008 Brian Moorhouse cert. ("less than ten copies of this variety are known") (Cat No. 62var) (Image)

Est.US$5,000