Mining hardware manufacturer Advanced Mining Technology, Inc. (AMT) is the latest to face a class-action lawsuit from customers alleging products were not delivered on time, according to a report in the Delaware County Daily Times.

There are concerns lawsuits could soon become more common in this field, in which small startup companies race to design and build cutting-edge and specialist hardware, dealing with processes that can challenge even large chip manufacturers.

Just over a week ago, a Texas judge granted a court order to 'freeze' the bitcoin wallets of another ASIC mining manufacturer, HashFast, as part of a lawsuit claiming late delivery. Butterfly Labs has been the target of both planned and actual legal action for over a year now.

Timing is perhaps even more critical in the world of bitcoin mining, where expensive machines delivered even a month or two late are rendered obsolete with no other useful purpose once mining becomes impractical.

The plaintiffs filed a complaint in the US District Court for the Eastern District of Pennsylvania last Wednesday, claiming the Haverford, Pennsylvania, startup is a "sham" company unwilling or unable to deliver its ASIC mining hardware on time.

The class action brings together plaintiffs from Florida, North Carolina and Utah, all of whom claimed they purchased ASIC hardware from AMT in November and December 2013, which was never delivered. They also claim there are hundreds of other AMT customers in the same boat.

They are requesting a jury trial based on claims of: "unfair, deceptive and fraudulent business practices, breach of contract, breach of express warranty, common law fraud, negligent misrepresentation, breach of the duty of good faith and fair dealing, unjust enrichment, and various state consumer protection laws."

A quick check of online forums indeed reveals some dissatisfied customers, and hints that the small company has struggled to meet the demands of large-scale customer service. On those same forums, however, AMT claims it is shipping products and has been posting regular updates in its official company news thread.

AMT, whose website slogan is 'Coin Mining on the Level', also sells on Amazon and has a catalogue that ranges from a compact 80 GH/s miner for $1,499 to a 3.2 TH/s beast for $14,999, with 20 units scheduled to ship on 15th April. It also sells its 28nm 'Coin Craft A1' chips and has said in forum posts it intends to offer a hosted mining option in future.

CoinDesk has reached out to AMT for further comment on this story, and will include it in an update if/when it arrives.