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  <xsd:element abstract="true" id="siga_statement-statement-note-13-equity-tables" name="statement-statement-note-13-equity-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="siga_statement-statement-note-14-leases-future-undiscounted-cash-flows-under-operating-leases-details" name="statement-statement-note-14-leases-future-undiscounted-cash-flows-under-operating-leases-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="siga_statement-statement-note-14-leases-tables" name="statement-statement-note-14-leases-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="siga_statement-statement-note-4-inventory-inventory-details" name="statement-statement-note-4-inventory-inventory-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="siga_statement-statement-note-4-inventory-tables" name="statement-statement-note-4-inventory-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="siga_statement-statement-note-5-property-plant-and-equipment-property-plant-and-equipment-details" name="statement-statement-note-5-property-plant-and-equipment-property-plant-and-equipment-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="siga_statement-statement-note-5-property-plant-and-equipment-tables" name="statement-statement-note-5-property-plant-and-equipment-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="siga_statement-statement-note-6-accrued-expenses-accrued-expenses-and-other-current-liabilities-details" name="statement-statement-note-6-accrued-expenses-accrued-expenses-and-other-current-liabilities-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="siga_statement-statement-note-6-accrued-expenses-and-other-current-liabilities-tables" name="statement-statement-note-6-accrued-expenses-and-other-current-liabilities-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="siga_statement-statement-note-8-per-share-data-reconciliation-of-the-basic-and-diluted-loss-per-share-details" name="statement-statement-note-8-per-share-data-reconciliation-of-the-basic-and-diluted-loss-per-share-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="siga_statement-statement-note-8-per-share-data-tables" name="statement-statement-note-8-per-share-data-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="siga_statement-statement-significant-accounting-policies-policies" name="statement-statement-significant-accounting-policies-policies" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
</xsd:schema>
