BPH Energy was out of favour with investors on Thursday, with its share price tumbling 50 per cent.

Its share price of 0.1c marks a new 52-week low for the stock (ASX:BPH), which has investments in biotechnology and resources.

In the second half of 2017, BPH widened its loss to $1.3 million and only had $225,130 cash in the kitty at the end of year.

BPH is now involved in a legal battle with stakeholder MEC Resources (ASX:MMR) over unpaid debts.

Earlier in April the company served energy investor MEC, which holds an 8.3 per cent interest in the company, with a writ issued in the District Court of Western Australia.

BPH shares over the past year.
BPH shares over the past year.

The head of BPH Energy, David Breeze, is the former managing director of MEC.

In the past year, BPH shares have only traded as high as 0.5c and that was in April last year.