A first edition of Karl Marx's "Das Kapital" fetched $40,000 in a digital sale on Amazon -owned AbeBooks earlier this month, The Guardian reported . The bookseller noted the irony in a blog post the day after the sale.

A critique of capitalism penned by the world's most noted Communist intellectual has garnered tens of thousands of dollars for a private owner.

"On the day that the Dow Jones index closed at an all-time high of 17,068 points, [we] sold a first edition of Karl Marx's Das Kapital for $40,000," the post read.



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The sale price was the site's second-highest of the year, The Guardian said. It noted that investment in antiques or fine art often goes in tandem with falling equities, which was far from the case when the buyer snatched the rare book.

In another twist, antique booksellers have complained that AbeBooks has extended their ability to sell niche products but simultaneously drains their business, The Guardian said.

Read The Guardian's full story here.

— By CNBC staff