. /.   WORLD TRADE  
ORGANIZATION  G/SPS/GEN/959 
1 September 2009 
 (09-4085) 
Committee on Sanitary a nd Phytosanitary Measures Original:   English 
  
 
OPTICAL WATERMARK ON EXPORT CERTIFICATES 
 
Submission by Singapore
 
  
 The following communication, received on 20 A ugust 2009, is being circulated at the request 
of the Delegation of Singapore
. 
 
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1. Singapore hereby notifies that the Agri-Food an d Veterinary Authority of Singapore (AVA) 
has developed an optical watermark system, to be a pplied to phytosanitary certificates, to be issued 
from 1 September 2009  onwards
.  It is likely that from this date certificates with optical watermark 
and the current certificates without the watermark ma y both be presented over a period of time.  This 
is due to the validity period of certificates issued prior to 1 September 2009.  Authorities of importing 
Members are familiar with AVA’s phytosanitary certif icates currently in use for plants and plant 
products, and Singapore hopes that the introduction of the optical watermark to these certificates will 
not cause any disruption to trade. 
2. More information on phytosanitary certificates w ith the optical watermark system is provided 
below. 
Phytosanitary Certificates with Optical Watermark System  
 
3. Certificates with the optical watermark will have the following physical security features that 
will distinguish them from certificates without th e watermark issued prior to 1 September 2009: 
(a) The optical watermark will comprise visible and invisible watermarks .  The visible 
watermark displays the AVA logo, while the invisible watermark has the word 
"COPY".  Both the visible and invisibl e watermarks will be embedded into the 
document and printed together with the document on a laser print.  When photocopied, the visible watermark (i.e. AVA logo) will appear diminished, while the invisible watermark will clearly appear.  To verify the authenticity of a certificate, when photocopied, the visible watermark should appear blurred, while the invisible 
watermark should be clearly seen.  No special decoding equipment is required for this 
verification process of the watermark as the watermark is visible to the naked eye. 
(b) There will be a microprint
 under the words "Agri-Food & Veterinary Authority of 
Singapore", at the top right hand of the certificate.  The microprint will appear as a very fine line on the certificate, which can only be viewed under a magnifying glass. 
The microprint comprises a repeating string of  the certificate number. It will appear 
distorted when photocopied to detect any unauthorized reproduction of the document. 
Sample copies of the certificates with and without the watermark may be obtained 
from the Singapore SPS Enquiry Point.  G/SPS/GEN/959 
Page 2  
 
   
(c) A 2D 
Barcode with the certificate information embedded into it will be printed on the 
upper right hand corner of the certificate.  Should importing authorities wish to verify 
the certificate, the 2D Barcode can be s canned, and the scanne d image uploaded for 
verification via the AVA's website. The Online Certificate Verification System 
(OCVS), newly developed by the AVA, will perform image processing on the image 
uploaded and decode the 2D Barcode.  Th e content of the document will then be 
presented, and this can be used to verify the integrity of the document. The URL for 
this is: https://www.psi.gov.sg/NASApp/tmf/TM FServlet?app=AVAECLIPS&isNew=true&
Reload=true&vs_StateMachine=Login .  
(d) The authorized signature on certificates bearing the optical watermark will be an 
electronic signature , and not signed by hand.  There will be no signature on the 
certificate attachments. 
4. The AVA has also developed an additional avenue for enquiries by authorities of importing 
Members, wishing to verify the authenticity of the certificates received. The Online Certificate 
Verification System (OCVS)  provides an authentication service for all certificates issued by the AVA 
using the optical watermark. Should the importing au thority wish to use the OCVS, a user ID and 
password will be issued upon request of the importin g authority.  These will give access to the OCVS.  
Upon entering the certificate number into the system , the OCVS will show the certificate details and 
verify that the certificate presented matches the cer tificate issued by the AVA.  (Note: Certificate 
attachments cannot be viewed on the OCVS.  To verify the attachments, the certificate number and 
date of issue printed at the top right hand corner of the attachment should match the accompanying certificate.) 
5. Should you have any questions, or should you wish to request the user ID and password for 
the OCVS, please do not hesitate to contact the Singapore SPS Enquiry Point
.   
 
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