Oracle shares were down as much as 3% during after-hours trading after the software company posted fiscal first-quarter revenue that came in under market observers' estimates.

Based on analysts' projections, Oracle's earnings came in at $1.03 a share, adjusted, against 97 cents a share, data by Refinitiv show.

The company reported revenue of $9.73 billion, against analysts' estimate of $9.77 billion, Refinitiv figures show. Analysts polled by FactSet had anticipated earnings of 97 cents per share on $9.75 billion sales.

Cloud Wars estimates that about $2 billion of Oracle's $13 billion in sales in 2020 were generated from Cloud.

Larry Ellison, Oracle executive chairman, and Safra Catz, chief executive officer have been pouring money on services to run users' applications and store their data in the Cloud after initially denigrating the space.

Ellison helped bankroll NetSuite in 1998 and his personal fortune is now estimated at around $117 billion, much of it in Oracle stock.

However, some clients are not yet totally bought to the idea of moving critical Oracle databases to the Cloud and may choose market leader or Microsoft Corp. when they do decide to shift, Bloomberg Intelligence Analyst Anurag Rana noted before results were disclosed.

Cloud technology is basically a more lucrative business compared to on-premise, and as the company look ahead to 2022, it estimates operating margins will remain unchanged or better than pre-pandemic levels, Catz said.

The company's two new Cloud businesses -- IaaS and SaaS -- are now more than a quarter of Oracle's total sales with a yearly run rate of $10 billion, Catz added.

Catz said Oracle's revenue in the current period will grow to around 3% to 5% compared from a year ago, hitting the average estimate of $10.1 billion. Profit will be $1.09 to $1.13 per share. On average, analysts were expecting $1.09.

"Estimates for Oracle would be for revenue forecasts to continue climbing," Jack Andrews, analyst at Needham & Co, said in quotes by Reuters.

Oracle's Cloud license and on-premises license segment generated $814 million in sales, retreating 8% and lower than the nearly $860 million analysts' estimates.

Oracle's hardware division posted $763 million in sales, down 6% and just under the $778.5 million figure expected by Wall Street.