January 1960 - December 1974 - Thorpe and Porter
On the 4th November 1959, the British government announced the end of import restrictions on cheap books and magazines from the USA which had been in place since the end of World War II. Following this, Thorpe and Porter (T&P) of Leicester became the first company to officially distribute US DC Comics in the UK. The first batch of books imported by T&P were cover dated October and November 1959 in the US, and likely hit shelves in the UK in January 1960.
T&P initially operated out of a warehouse on East Street, Oadby, Leicester. In 1965 they moved to a larger warehouse on Melton Road, Thurmaston, also in Leicester.
Unlike the distribution agreement Thorpe and Porter made with Marvel Comics - where new books were sent to the UK direct from the printer with various UK-specific cover and indicia amendments - the DC comics received in January 1960 were unsold US copies left over from the US newsstand distribution system - it's likely these were uncirculated copies rejected by dealers rather than comics that had sat on a newsstand in the US for a month, but this has yet to be confirmed. T&P continued to receive sporadic US returns - where issues could appear out of order, a given title might not appear in shipments for multiple months, or 2 or 3 issues of a title might appear all at once - until at least 1975, possibly later.
Who T&P were buying these returns from remains something of a mystery. The best current guesses are either one or multiple New York-area wholesalers, or Publisher's Surplus Corp. (PSC), a business set-up in 1925 to sell out of date and unsold US magazines overseas.
DC comics distributed by T&P in the UK were the standard US versions, not any kind of reprint or variant. As the imported comics only carried a US price on the cover, T&P ink-stamped the covers with a UK price - 9d when distribution began - a process they were already using for American magazines when the first comics arrived.
The only exception to this were 5 issues with cover dates July or August 1971, which carried a printed UK price. Contemporary fanzine accounts say this was a trial run due to changes in newsstand returns practices in the US - T&P were unsure whether importing US returns would remain a viable distribution channel going forward. The experiment did not continue after the initial batch of 5 issues, and there wouldn't be another US DC issue with a printed UK price until 1978. Cents priced copies of all 5 of the 1971 UK price variants were also distributed in the UK with T&P stamps.
Around July 1966, Thorpe and Porter were purchased out of receivership by Independent News Co., a division of DC's parent company National Periodical Publications (NPP) and the newsstand distributor of DC comics in the USA. A year later in July 1967, Kinney National Service, Inc. purchased NPP. In February 1972, Kinney reincorporated as Warner Communications, Inc. In October 1974, Warner announce that they had sold their UK interests - Thorpe and Porter, Brown Watson and Murray Book Sales - to publishing conglomerate Howard & Wyndham.
In early 1975, Howard & Wyndham reorganised the Thorpe and Porter business, renaming the comics and magazine distribution arm General Book Distributors Ltd.
January 1975 - December 1976 - General Book Distributors
Under the new owners and with a new name, the UK distribution of DC comics into newsagents continued much as it had previously, run by the same people and operating out of the same premises in Thurmaston, Leicester.
A contemporary UK fanzine report suggests that, at some point in 1975, General Book Distributors started to receive new, uncirculated run-on copies of DC comics direct from the printers, in addition to the returns that they'd been importing into the UK since 1960.
In December 1976, Howard & Wyndham sold General Book Distributors to Petbridge Limited, based in Surrey and owned by brothers Ralph and David Gold, best known these days as publishers of the Sunday Sport and former co-owners of West Ham United. Through the 60's and early 70's, the Gold brothers had built an extremely successful top-shelf magazine publishing and distribution empire. Via their Gold Star Publishing business, they'd been involved in importing American comics from various publishers into the UK since the mid-60's, at least. Howard & Wyndham retained ownership of General Book Distributors (Top Sellers) Limited - Thorpe and Porter's former comics and magazine publishing arm - necessitating a change in trading style for the distribution business to 'GB Distributors, a division of Petbridge Limted', or GBD.
January 1977 - September 1999 - GB Distributors / GBD / Moore Harness / Portman Distribution
GB Distributors (GBD) initially operated out of the same warehouse complex on Melton Road, Thurmaston that Thorpe & Porter had been operating in since 1965. Circa 1978 they moved to a smaller warehouse a stones throw away on the same industrial estate, on Norman Road, Thurmaston. This was likely in anticipation of Howard & Wyndham shuttering the old Melton Road warehouse in 1979, at which point it was taken over by Walkers Crisps.
In the late 70's, GBD's parent company Petbridge Ltd acquired or took control of Moore Harness Ltd (the Gold brothers may have had a minority ownership interest in Moore Harness prior to this), Moore Harness were probably best known as distributors of Private Eye and 60's underground magazine Oz. The Gold's folded Moore Harness into Petbridge, and at some point prior to 1990, the DC distribution operation moved under Moore Harness' remit. Circa 1993 it transferred to Portman Distribution, another Petbridge division which seems to have lain dormant through the 80's after distributing a handful of horror comics in 1978/79.
From 1978 through 1999 - regardless of whether the distributor on paper was GBD, Moore Harness or Portman - the same people were running the operation out of the same premises on Norman Road, Thurmaston.
Beginning with DC comics cover dated February 1978, DC's printers (World Color, of Sparta, IL) produced a UK-specific variant of new issues that carried a pence cover price (12p at that time). Presumably this is when GBD moved to importing solely new comics direct from World Color, and stopped importing returns entirely. The last UK-specific variant covers appeared on books cover dated to September 1981.
No over-sized issues were produced with printed pence prices, though some were distributed with a UK price ink-stamped on the cover. Steve Cranch has compiled a list of all of the DC UK Price Variants produced from 1978 to 1981 here.
For DC Comics cover dated October 1981 to November 1995, Direct Sales editions of most of DC's standard format books carried a UK price in the corner box. Almost all standard format titles were distributed in the UK, including over-sized issues. From the late 80's onward, most comics that did not carry a UK cover price (eg Legends of the Dark Knight and the Prestige Format books) were distributed in newsagents with a price-gun sticker carrying a UK price. It's currently unclear whether the 'Baxter' books published earlier in the 80's (New Teen Titans, Legion of Super-Heroes, etc.) or the first tranche of Prestige Format books (The Dark Knight, Green Arrow: The Longbow Hunters, etc) were distributed in UK newsagents or not. If they were it was likely on a regional basis.
From circa April 1987 (the introduction of DC's 'New Format') through April 1995, the vast majority of DC's publishing output - including books that were Direct Sales only in the USA - were distributed to UK newsagents. Anything that didn't have a UK printed price on the cover carried a price sticker.
In April 1995, DC Comics announced an exclusive Direct Market distribution deal with Diamond Distributors in the US. After what I assume was a 6-month grace period, this heavily curtailed UK newsagent distribution - perhaps because GBD were technically a Direct Market customer of DC's, despite the fact that they operated in the UK newsagent trade on a Sale of Return basis? The last month of DC books to carry UK cover prices were cover dated November 1995. There are a handful of stragglers - a couple of books that shipped late and a couple where it looks like the printer just forgot to take the UK price off the plate - but this is the last month where the UK cover price spans the whole line. The range of titles on offer was also drastically reduced beginning with books cover dated December 1995, going from essentially everything DC published to a fixed quantity of 40 titles per month, inclusive of all annuals, mini-series, specials etc.
Comics cover dated December 1995 to June 1996 that were distributed in UK newsagents carried a UK cover price on a price-gun sticker. From July 1996 to October 1997, small printed stickers were used for £1.25 and £1.50 books (the vast majority of the range) and price stickers were used for books priced £2.00 and above. From October 1997 to circa September 1998, UK distributed issues carried a large barcode sticker with the price and sometimes the issue number printed on it - more expensive comics outside of the £1.25/£1.50 price scheme were no longer distributed. From circa October 1998 to September 1999, all issues in a given month carried a generic barcode sticker with the same number on it for all titles (eg the barcode for all of the September 1999 cover-dated books says 'ISSUE NO. 12').
UK newsagent distribution of US-published DC comics ended with issues cover dated September 1999. My research suggests that, by September '99 the range of books distributed in the UK was, probably at most, 9 titles all priced $1.99/£1.50, of which 3 (Superboy (pictured above), Detective Comics, and Young Justice) have been confirmed.
Up to August 1998 it's fairly easy to find examples of all of these. After that distribution seems to drop off a cliff - for September 1998 I've only found 2 books. For October '98, January '99 and April '99 so far I've found none.
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From the early 90's to around 1997, Portman sold their returns and overstocks en masse to the Comics Warehouse, a back issue mail-order outlet based in Maldon, Essex who used to run regular adverts in Comics International offering tat like Armageddon: The Alien Agenda for 10p an issue. Prior to this, returns and overstocks had been periodically discounted and recirculated into newsagents, particularly in coastal resorts, stretching right back into the Thorpe and Porter era. I think Comics Warehouse may have stopped taking Portman's overstocks when they started using the barcode stickers. Overstocks and returns that remained in the Portman warehouse when distribution ended were discounted with large yellow stickers reading either 'Price 99p' or 'Two DC Comics for Only 99p' and circulated to newsagents and remainder book shops like The Works.
Though not technically a newsagent, mass-market bookstore chain Borders did carry a selection of US DC comics distributed by Diamond UK. As far as I can remember these were standard US Direct editions with no additional stickers or stamps. Borders opened their first UK store in London's Oxford Street in August 1998 and collapsed into administration in 2009, with all of their remaining stores closing by the end of that year.