<SEC-DOCUMENT>0001367644-21-000018.txt : 20210211
<SEC-HEADER>0001367644-21-000018.hdr.sgml : 20210211
<ACCEPTANCE-DATETIME>20210211212413
ACCESSION NUMBER:		0001367644-21-000018
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20210209
FILED AS OF DATE:		20210211
DATE AS OF CHANGE:		20210211

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Havey Adam
		CENTRAL INDEX KEY:			0001514588

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-33137
		FILM NUMBER:		21622209

	MAIL ADDRESS:	
		STREET 1:		2273 RESEARCH BLVD SUITE 400
		CITY:			ROCKVILLE
		STATE:			MD
		ZIP:			20853

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			Emergent BioSolutions Inc.
		CENTRAL INDEX KEY:			0001367644
		STANDARD INDUSTRIAL CLASSIFICATION:	PHARMACEUTICAL PREPARATIONS [2834]
		IRS NUMBER:				141902018
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		400 PROFESSIONAL DR, SUITE 400
		CITY:			GAITHERSBURG
		STATE:			MD
		ZIP:			20879
		BUSINESS PHONE:		240-631-3200

	MAIL ADDRESS:	
		STREET 1:		400 PROFESSIONAL DR, SUITE 400
		CITY:			GAITHERSBURG
		STATE:			MD
		ZIP:			20879
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>wf-form4_161309662486709.xml
<DESCRIPTION>FORM 4
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2021-02-09</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001367644</issuerCik>
        <issuerName>Emergent BioSolutions Inc.</issuerName>
        <issuerTradingSymbol>EBS</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001514588</rptOwnerCik>
            <rptOwnerName>Havey Adam</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>400 PROFESSIONAL DR, SUITE 400</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>GAITHERSBURG</rptOwnerCity>
            <rptOwnerState>MD</rptOwnerState>
            <rptOwnerZipCode>20879</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>EVP, Business Operations</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
                <footnoteId id="F1"/>
            </securityTitle>
            <transactionDate>
                <value>2021-02-09</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>2518</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>35203</value>
                    <footnoteId id="F2"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
                <footnoteId id="F3"/>
            </securityTitle>
            <transactionDate>
                <value>2021-02-09</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>F</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>2183</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>123.45</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>33020</value>
                    <footnoteId id="F2"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">Consists of Performance Stock Units (&quot;PSUs&quot;) previously granted on February 27, 2018 under the company's stock incentive plan as amended and restated. Each PSU represents the right to receive one share of common stock, which vested at a specified percentage based upon achievement with respect to adjusted net income as a percentage of total GAAP revenue for the 2020 fiscal year, as certified by the Compensation Committee following the performance period. On February 9, 2021, the Compensation Committee certified the achievement of the 2018-2020 PSUs at a payout factor of 150% of target resulting in the actual award of 7,554 shares of common stock, which is in excess of the 5,036 shares previously reported on March 1, 2018.</footnote>
        <footnote id="F2">The number of derivative securities beneficially owned was adjusted to account for a change in previously reported PSUs. 4,285 PSUs were previously reported, of which only 2,714 vested on February 11, 2020.</footnote>
        <footnote id="F3">Represents shares of common stock withheld to pay taxes due upon vesting of the PSUs.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ S. Scott Lieberman, Attorney-in-fact</signatureName>
        <signatureDate>2021-02-11</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
