Blocklisting Interim Review

Name of applicant:

SPIRENT COMMUNICATIONS PLC

Name of scheme:

SPIRENT EXECUTIVE SHARE OPTION SCHEME, 1995

Period of return:

From:

01-JAN-08

To:

30-JUN-08

Balance of unallotted securities under scheme(s) from previous return:

2,147,600 ORDINARY SHARES OF 3 1/3p EACH

Plus: The amount by which the block scheme(s) has been increased since the date of the last return (if any increase has been applied for):

NIL

Less: Number of securities issued/allotted under scheme(s) during period (see LR3.5.7G):

322,400 ORDINARY SHARES OF 3 1/3p EACH

Equals: Balance under scheme(s) not yet issued/allotted at end of period:

1,825,200 ORDINARY SHARES OF 3 1/3p EACH

Name of contact:

WARREN NASH

Telephone number of contact:

01293 767657

Name of applicant:

SPIRENT COMMUNICATIONS PLC

Name of scheme:

SPIRENT EMPLOYEE INCENTIVE PLAN 2005

Period of return:

From:

01-JAN-08

To:

30-JUN-08

Balance of unallotted securities under scheme(s) from previous return:

3,187,159 ORDINARY SHARES OF 3 1/3p EACH

Plus: The amount by which the block scheme(s) has been increased since the date of the last return (if any increase has been applied for):

NIL

Less: Number of securities issued/allotted under scheme(s) during period (see LR3.5.7G):

13,371 ORDINARY SHARES OF 3 1/3p EACH

Equals: Balance under scheme(s) not yet issued/allotted at end of period:

3,173,788 ORDINARY SHARES OF 3 1/3p EACH

Name of contact:

WARREN NASH

Telephone number of contact:

01293 767657

Name of applicant:

SPIRENT COMMUNICATIONS PLC

Name of scheme:

SPIRENT STOCK INCENTIVE PLAN

Period of return:

From:

01-JAN-08

To:

30-JUN-08

Balance of unallotted securities under scheme(s) from previous return:

1,315,950 ORDINARY SHARES OF 3 1/3p EACH

Plus: The amount by which the block scheme(s) has been increased since the date of the last return (if any increase has been applied for):

2,500,000 ORDINARY SHARES OF 3 1/3p EACH

Less: Number of securities issued/allotted under scheme(s) during period (see LR3.5.7G):

646,072 ORDINARY SHARES OF 3 1/3p EACH

Equals: Balance under scheme(s) not yet issued/allotted at end of period:

3,169,878 ORDINARY SHARES OF 3 1/3p EACH

Name of contact:

WARREN NASH

Telephone number of contact:

01293 767657

Name of applicant:

SPIRENT COMMUNICATIONS PLC

Name of scheme:

U.S. EMPLOYEE STOCK PURCHASE PLAN

Period of return:

From:

01-JAN-08

To:

30-JUN-08

Balance of unallotted securities under scheme(s) from previous return:

1,237,364 ORDINARY SHARES OF 3 1/3p EACH

Plus: The amount by which the block scheme(s) has been increased since the date of the last return (if any increase has been applied for):

NIL

Less: Number of securities issued/allotted under scheme(s) during period (see LR3.5.7G):

NIL

Equals: Balance under scheme(s) not yet issued/allotted at end of period:

1,237,364 ORDINARY SHARES OF 3 1/3p EACH

Name of contact:

WARREN NASH

Telephone number of contact:

01293 767657

Name of applicant:

SPIRENT COMMUNICATIONS PLC

Name of scheme:

SPIRENT GLOBAL ALL EMPLOYEE SHARE PURCHASE PLAN

Period of return:

From:

01-JAN-08

To:

30-JUN-08

Balance of unallotted securities under scheme(s) from previous return:

814,444 ORDINARY SHARES OF 3 1/3p EACH

Plus: The amount by which the block scheme(s) has been increased since the date of the last return (if any increase has been applied for):

NIL

Less: Number of securities issued/allotted under scheme(s) during period (see LR3.5.7G):

NIL

Equals: Balance under scheme(s) not yet issued/allotted at end of period:

814,444 ORDINARY SHARES OF 3 1/3p EACH

Name of contact:

WARREN NASH

Telephone number of contact:

01293 767657

Name of applicant:

SPIRENT COMMUNICATIONS PLC

Name of scheme:

SPIRENT SAVINGS RELATED SHARE OPTION SCHEME

Period of return:

From:

01-JAN-08

To:

30-JUN-08

Balance of unallotted securities under scheme(s) from previous return:

68,185 ORDINARY SHARES OF 3 1/3p EACH

Plus: The amount by which the block scheme(s) has been increased since the date of the last return (if any increase has been applied for):

NIL

Less: Number of securities issued/allotted under scheme(s) during period (see LR3.5.7G):

NIL

Equals: Balance under scheme(s) not yet issued/allotted at end of period:

68,185 ORDINARY SHARES OF 3 1/3p EACH

Name of contact:

WARREN NASH

Telephone number of contact:

01293 767657

Name of applicant:

SPIRENT COMMUNICATIONS PLC

Name of scheme:

NETCOM AMENDED AND RESTATED STOCK OPTION PLAN

Period of return:

From:

01-JAN-08

To:

30-JUN-08

Balance of unallotted securities under scheme(s) from previous return:

1,570,054 ORDINARY SHARES OF 3 1/3p EACH

Plus: The amount by which the block scheme(s) has been increased since the date of the last return (if any increase has been applied for):

NIL

Less: Number of securities issued/allotted under scheme(s) during period (see LR3.5.7G):

NIL

Equals: Balance under scheme(s) not yet issued/allotted at end of period:

1,570,054 ORDINARY SHARES OF 3 1/3p EACH

Name of contact:

WARREN NASH

Telephone number of contact:

01293 767657

Name of applicant:

SPIRENT COMMUNICATIONS PLC

Name of scheme:

ZARAK AMENDED AND RESTATED STOCK OPTION PLAN

Period of return:

From:

01-JAN-08

To:

30-JUN-08

Balance of unallotted securities under scheme(s) from previous return:

2,690,996 ORDINARY SHARES OF 3 1/3p EACH

Plus: The amount by which the block scheme(s) has been increased since the date of the last return (if any increase has been applied for):

NIL

Less: Number of securities issued/allotted under scheme(s) during period (see LR3.5.7G):

NIL

Equals: Balance under scheme(s) not yet issued/allotted at end of period:

2,690,996 ORDINARY SHARES OF 3 1/3p EACH

Name of contact:

WARREN NASH

Telephone number of contact:

01293 767657

Name of applicant:

SPIRENT COMMUNICATIONS PLC

Name of scheme:

CAW AMENDED AND RESTATED STOCK OPTION PLAN

Period of return:

From:

01-JAN-08

To:

30-JUN-08

Balance of unallotted securities under scheme(s) from previous return:

777,666 ORDINARY SHARES OF 3 1/3p EACH

Plus: The amount by which the block scheme(s) has been increased since the date of the last return (if any increase has been applied for):

NIL

Less: Number of securities issued/allotted under scheme(s) during period (see LR3.5.7G):

NIL

Equals: Balance under scheme(s) not yet issued/allotted at end of period:

777,666 ORDINARY SHARES OF 3 1/3p EACH

Name of contact:

WARREN NASH

Telephone number of contact:

01293 767657