One of this year's off-the-radar winners has been RingCentral (RNG -1.22%). Shares of the company behind a next-gen telco platform entered this trading week with a 75% year-to-date gain. You probably have never heard of RingCentral despite it being a 14-bagger since the start of 2017, but another blowout financial report this week could start to turn heads. 

Shares of RingCentral opened higher on Tuesday after it delivered its third-quarter results. Revenue and earnings exceeded expectations, and the company lifted its top- and bottom-line guidance for the year. This is old hat for RingCentral. It has now topped analyst profit targets for 12 consecutive quarters. If RingCentral isn't on your investing radar, you may want to find one with a larger screen to make sure that the quiet market winner is pinging for you.

RingCentral running on an IP phone, laptop, smartphone, and tablet.

Image source: RingCentral.

Ringing in your ears

Revenue rose 30% to hit $303.6 million, accelerating from the 29% year-over-year gain it posted in the second quarter and well above the 23% increase that Wall Street pros were expecting. The heart of RingCentral's business is growing even faster. Subscription revenue -- accounting for 92% of the top-line mix here -- surged 33% for the quarter. The annualized exit monthly recurring subscriptions and the annualized run rate of its RingCentral Office platform are growing even faster, up 34% and 36%, respectively.

The news is also encouraging at the other end of the income statement. The adjusted profit of $0.26 per share was ahead of both the $0.22 per share it posted a year earlier and the $0.24 per share that analysts were targeting. 

RingCentral's cloud-based platform is making a lot of sense to companies that find their workforce toiling outside of the office. Companies pay $19.99 a month or more for the service where inbound calls are automatically routed to IP phones, mobile devices, PCs, or videoconferencing rooms. With employees spending more time out of the office these days, it's easy to see why RingCentral has thrived during the shelter-in-place phase of the pandemic. Its shares retreating nearly 10% on Monday solidifies its status as a stay-at-home stock. However, RingCentral has always been more than a COVID-19 play.

RingCentral's new guidance calls for revenue growth of 29% for all of 2020, decelerating to between a 25% and 26% increase in the current quarter. Thankfully this is a company that routinely puts out conservative guidance, so this should be the fourth year in a row that revenue grows by at least 30%.

RingCentral has been thriving as a subscription-based enterprise platform for companies where portability mattered long before it was required in the new normal. It's no stodgy telecom stock. The sell-off on Monday is proving to be a buying opportunity, and the market's favorable reaction to another "beat and raise" performance validates the notion that RingCentral is a stock that you should buy on weakness instead of selling into strength.