FOR IMMEDIATE RELEASE

17 October 2025

SPIRENT COMMUNICATIONS PLC

DE-LISTING AND CANCELLATION OF TRADING OF SPIRENT SHARES

Further to the announcement made by Keysight Technologies Inc. and Spirent Communications plc ("Spirent") on 15 October 2025 in respect of the Scheme becoming Effective, Spirent today announces that, following an application by Spirent, the Financial Conduct Authority has cancelled the listing of Spirent Shares on the Official List and the London Stock Exchange has cancelled the trading of the Spirent Shares on the London Stock Exchange's main market for listed securities, in each case with effect from 7:30 a.m. today (London time).

Defined terms used but not defined in this announcement have the meanings set out in the Scheme Document dated 25 April 2024.

Enquiries

Linklaters LLP is retained as legal adviser to Spirent.

Important Notices

UBS AG London Branch ("UBS") is authorised and regulated by the Financial Market Supervisory Authority in Switzerland. It is authorised by the Prudential Regulation Authority and subject to regulation by the Financial Conduct Authority and limited regulation by the Prudential Regulation Authority in the UK. UBS is acting exclusively as corporate broker and financial adviser to Spirent and no one else in connection with the Acquisition. In connection with such matters, UBS will not regard any other person as its client, nor will it be responsible to any other person for providing the protections afforded to its clients or for providing advice in relation to the Acquisition, the contents of this announcement or any other matter referred to herein.

N.M. Rothschild & Sons Limited ("Rothschild & Co"), which is authorised and regulated by the Financial Conduct Authority in the UK, is acting exclusively as financial adviser to Spirent and no one else in connection with the Acquisition and will not be responsible to anyone other than Spirent for providing the protections afforded to clients of Rothschild & Co nor for providing advice in connection with the Acquisition or any matter referred to herein. Neither Rothschild & Co nor any of its affiliates (nor their respective directors, officers, employees or agents) owes or accepts any duty, liability or responsibility whatsoever (whether direct or indirect, whether in contract, in tort, under statute or otherwise) to any person who is not a client of Rothschild & Co in connection with this announcement, any statement contained in this announcement, the acquisition of Spirent or otherwise. No representation or warranty, express or implied, is made by Rothschild & Co as to the contents of this announcement.

Jefferies International Limited ("Jefferies") is authorised and regulated in the UK by the Financial Conduct Authority. Jefferies is acting exclusively as financial adviser and corporate broker to Spirent and no one else in connection with the Acquisition and will not be responsible to anyone other than Spirent for providing the protections afforded to clients of Jefferies nor for providing advice in connection with the Acquisition or any matter referred to herein. Neither Jefferies nor any of its affiliates (nor their respective directors, officers, employees or agents) owes or accepts any duty, liability or responsibility whatsoever (whether direct or indirect, whether in contract, in tort, under statute or otherwise) to any person who is not a client of Jefferies in connection with this announcement, any statement contained in this announcement, the Acquisition or otherwise. No representation or warranty, express or implied, is made by Jefferies as to the contents of this announcement.

Publication on Website

In accordance with Rule 26.1 of the Takeover Code, a copy of this announcement will be made available, subject to certain restrictions relating to persons resident in restricted jurisdictions, on Spirent's website at https://corporate.spirent.com by no later than 12 noon (London time) on the business day following the date of this announcement. For the avoidance of doubt, the contents of this website are not incorporated into and do not form part of this announcement.