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Investor Relations : Jess Lubert Juniper Networks ( 408 ) 936-3734 jlubert@juniper.net Media Relations : Leslie Moore Juniper Networks ( 408 ) 936-5767 Exhibit 99.1 Ilmoore@juniper.net JUNIPER NETWORKS REPORTS PRELIMINARY FIRST QUARTER 2021 FINANCIAL RESULTS SUNNYVALE , Calif . , April 27 , 2021 - Juniper Networks ( NYSE : JNPR ) , a leader in secure , AI - driven networks , today reported preliminary financial results for the three months ended March 31 , 2021 and provided its outlook for the three months ending June 30 , 2021 . First Quarter 2021 Financial Performance Net revenues were $ 1,074.4 million , an increase of 8 % year - over - year and a decrease of 12 % sequentially . GAAP operating margin was 2.6 % , a decrease from 3.9 % in the first quarter of 2020 , and a decrease from 8.0 % in the fourth quarter of 2020 . Non - GAAP operating margin was 12.1 % , an increase from 10.2 % in the first quarter of 2020 , and a decrease from 19.3 % in the fourth quarter of 2020 . GAAP net loss was $ 31.1 million , a decrease of 252 % year - over - year and 201 % sequentially , resulting in diluted loss per share of $ 0.10 . Non - GAAP net income was $ 98.5 million , an increase of 28 % year - over - year , and a decrease of 46 % sequentially , resulting in non - GAAP diluted earnings per share of $ 0.30 . The reconciliation between GAAP and non - GAAP results of operations is provided in a table immediately following the Preliminary Net Revenues by Geographic Region table below . " We reported strong March quarter results . Revenue exceeded our expectations and we experienced better than expected product orders across each of our customer verticals , " said Juniper's CEO , Rami Rahim . “ Momentum is strong entering the June quarter and we are confident regarding our growth prospects . We believe the success we are seeing is a result of the deliberate actions we have taken to strengthen our product portfolio and go - to - market organization , both of which are enabling us to capitalize on attractive end - market opportunities now and in the future . " " We delivered a strong financial performance during the March quarter as revenue , non - GAAP operating margin and non - GAAP earnings per share each exceeded our expectations , ” said Juniper's CFO , Ken Miller . “ Backlog grew both sequentially and year - over - year and near- term visibility is strong . We believe the investments we have made are paying off and should enable us to not only return to sustained revenue growth , but also to deliver improved profitability over time . " Page 1 of 12