Square priced its IPO below what was already considered a conservative range, as it struggled to win over sceptical investors.

Square’s stock, which begin trading today (19 November), was priced at $9 per share, below the previously announced range of $11-13 per share.

The offering puts a valuation of approximately $3 billion on the firm, which just a year ago was valued at $6 billion following a Series E fundraising in October 2014. The current valuation does not take account of future shares issued to employees.

Investors have various concerns about the firm, which enables small businesses to process card payments by adding a dongle to a smartphone or tablet. There is also a more widespread caution towards the valuations placed on tech firms in general.

Despite being a fast-growing business, in terms of revenue growth, Square is loss-making. It also faces a number of significant competitors in the mobile point-of-sale (MPoS) market, including PayPal. MPoS is a business with low entry barriers.

Square will also have to compensate for the end of a transaction-processing contract with Starbucks, its largest customer. The risk of fraud is another factor concerning investors, as well as the position of CEO Jack Dorsey, who divides his time between Square and an equally demanding role as CEO of Twitter.

The $9 price will trigger a guarantee Square made to investors in the past funding round which gives them additional shares if the IPO price was below $18.55. As compensation, late-stage investors will double their allocation of shares.