Filing obligations for draft offer documents require lead manager due diligence and Board observation compliance before IPO completion. Regulation 25 requires issuers, via lead manager(s), to file the draft offer document with the Board and with proposed listing stock exchange(s), accompanied by engagement and due diligence certificates (including a debenture trustee certificate for convertible debt) and prescribed fees. The Board may issue observations within a thirty-day period measured from specified triggering events; issuers and lead managers must incorporate such observations and file updated drafts. After filing with the Registrar, the offer document and abridged prospectus must be filed with the Board and exchanges in soft copy, and lead managers must submit compliance certifications, due diligence and auditor certificates, and board resolutions as applicable.