Amazon Soars as Digital Sales Support Margins Inc’s stellar quarterly results are helping convince skeptics on Wall Street that a bout of intense spending is beginning to pay off for an Internet retailer trying to transform itself into a technology company.

Shares in Amazon leapt 15 percent on Friday after it reported first-quarter earnings and margins well above investors’ most bullish expectations, tacking on some $10 billion in market value and marking its biggest single-day gain since October of 2009.

CEO Jeff Bezos has tried to convince investors to stick with the company for the long term as it flirted with losses in recent quarters.

He is trying to transform Amazon from an online version of a big-box retailer like Wal-Mart into a provider of technology services.

Some investors argue that its valuation of over 70 times forward earnings – dwarfing companies like Apple Inc and Google Inc that produce record profits – is justified because Amazon is on track for enormous margin expansion as it expands into more-profitable services from hosting websites in the cloud to providing an online marketplace connecting buyers and sellers.

Amazon is trying to be “not a bookseller or a retailer, but a company that uses technology, and now its scale to transform whole value chains” from retail to publishing and video distribution, as Reuters stated.

Amazon shares rose to $225.75 on the Nasdaq.

That surprise increase in gross margins prompted a flurry of price target increases by analysts.

Faster growth at its online marketplace business and cloud unit Amazon Web Services, along with sales of digital goods, drove the improvement in margins, analysts said.

Amazon’s 34 percent revenue increase to $13.18 billion also impressed Wall Street which had expected revenue of $12.9 billion, according to Thomson Reuters I/B/E/S.

During the first quarter, nine of the 10 top-selling products on were digital products, including Kindle e-books, movies, music and apps.

The company’s shares had been hit by margin pressure over the past few quarters.