Holding(s) in Company

TR-1: NOTIFICATION OF MAJOR INTEREST IN SHARESi

1. Identity of the issuer or the underlying issuerof existing shares to which voting rights areattached: ii

Opsec Security Group Plc

2 Reason for the notification (please tick the appropriate box or boxes):

An acquisition or disposal of voting rights

P

An acquisition or disposal of qualifying financial instruments which may result in the acquisition of shares already issued to which voting rights are attached

An acquisition or disposal of instruments with similar economic effect to qualifying financial instruments

An event changing the breakdown of voting rights

Other (please specify):

3. Full name of person(s) subject to thenotification obligation: iii

Herald Investment Management Limited

4. Full name of shareholder(s)  (if different from 3.):iv

5. Date of the transaction and date onwhich the threshold is crossed orreached: v

28th July 2011

6. Date on which issuer notified:

29th July 2011

7. Threshold(s) that is/are crossed orreached: vi, vii

24%

8. Notified details:

A: Voting rights attached to shares viii, ix

Class/type ofshares

if possible usingthe ISIN CODE

Situation previousto the triggeringtransaction

Resulting situation after the triggering transaction

NumberofShares

NumberofVotingRights

Numberof shares

Number of votingrights

% of voting rights x

Indirect

Direct xi

Indirect xii

Direct

Indirect

GB0000462191

18,064,274

18,064,274

18,275,100

18,275,100

24.03%

B: Qualifying Financial Instruments

Resulting situation after the triggering transaction

Type of financialinstrument

Expirationdate xiii

Exercise/Conversion Period xiv

Number of votingrights that may beacquired if theinstrument isexercised/ converted.

% of votingrights

None

Nil

C: Financial Instruments with similar economic effect to Qualifying Financial Instruments xv, xvi

Resulting situation after the triggering transaction

Type of financialinstrument

Exercise price

Expiration date xvii

Exercise/Conversion period xviii

Number of voting rights instrument refers to

% of voting rights xix, xx

None

Nominal

Delta

Nil

Total (A+B+C)

Number of voting rights

Percentage of voting rights

18,275,100

24.03%

9. Chain of controlled undertakings through which the voting rights and/or thefinancial instruments are effectively held, if applicable: xxi

N/A

Proxy Voting:

10. Name of the proxy holder:

N/A

11. Number of voting rights proxy holder will ceaseto hold:

N/A

12. Date on which proxy holder will cease to holdvoting rights:

N/A

13. Additional information:

14. Contact name:

Andrew Miller CFO

15. Contact telephone number:

020 7553 6308

Note: Annex should only be submitted to the FSA not the issuer

Annex: Notification of major interests in share

A: Identity of the persons or legal entity subject to the notification obligation

Full name

(including legal form of legal entities)

Herald Investment Management Limited

Contact address

(registered office for legal entities)

10/11 Charterhouse Square

London EC1M 6EE

Phone number & email

020 7553 6308

Other useful information

(at least legal representative for legal persons)

Andrew Miller

B: Identity of the notifier, if applicable

Full name

See Above

Contact address

Phone number & email

Other useful information

(e.g. functional relationship with the person or legal entity subject to the notification obligation)

C: Additional information

We have used the total number of voting rights in issue of 76,045,858 (56,045,858 ordinary shares and 20,000,000 preferred voting shares) as advised to us by the company's finance director on 7th April 2011 to calculate the percentage of voting rights after the triggering transaction.

For notes on how to complete form TR-1 please see the FSA website.