diff --git a/apps/files_sharing/lib/Controller/ShareAPIController.php b/apps/files_sharing/lib/Controller/ShareAPIController.php
index 1bdcee11c45..36a515bf29d 100644
--- a/apps/files_sharing/lib/Controller/ShareAPIController.php
+++ b/apps/files_sharing/lib/Controller/ShareAPIController.php
@@ -549,7 +549,8 @@ class ShareAPIController extends OCSController {
 	 * @param string $publicUpload If public uploading is allowed
 	 * @param string $password Password for the share
 	 * @param string|null $sendPasswordByTalk Send the password for the share over Talk
-	 * @param string $expireDate Expiry date of the share using user timezone at 00:00. It means date in UTC timezone will be used.
+	 * @param ?string $expireDate The expiry date of the share in the user's timezone (UTC) at 00:00.
+	 *                If $expireDate is not supplied or set to `null`, the system default will be used.
 	 * @param string $note Note for the share
 	 * @param string $label Label for the share (only used in link and email)
 	 * @param string|null $attributes Additional attributes for the share
@@ -571,7 +572,7 @@ class ShareAPIController extends OCSController {
 		string $publicUpload = 'false',
 		string $password = '',
 		?string $sendPasswordByTalk = null,
-		string $expireDate = '',
+		?string $expireDate = null,
 		string $note = '',
 		string $label = '',
 		?string $attributes = null
@@ -646,12 +647,18 @@ class ShareAPIController extends OCSController {
 		}
 
 		//Expire date
-		if ($expireDate !== '') {
-			try {
-				$expireDateTime = $this->parseDate($expireDate);
-				$share->setExpirationDate($expireDateTime);
-			} catch (\Exception $e) {
-				throw new OCSNotFoundException($this->l->t('Invalid date, date format must be YYYY-MM-DD'));
+		if ($expireDate !== null) {
+			if ($expireDate !== '') {
+				try {
+					$expireDateTime = $this->parseDate($expireDate);
+					$share->setExpirationDate($expireDateTime);
+				} catch (\Exception $e) {
+					throw new OCSNotFoundException($this->l->t('Invalid date, date format must be YYYY-MM-DD'));
+				}
+			} else {
+				// Client sent empty string for expire date.
+				// Set noExpirationDate to true so overwrite is prevented.
+				$share->setNoExpirationDate(true);
 			}
 		}
 
@@ -768,19 +775,19 @@ class ShareAPIController extends OCSController {
 			$share->setPermissions($permissions);
 		} elseif ($shareType === IShare::TYPE_ROOM) {
 			try {
-				$this->getRoomShareHelper()->createShare($share, $shareWith, $permissions, $expireDate);
+				$this->getRoomShareHelper()->createShare($share, $shareWith, $permissions, $expireDate ?? '');
 			} catch (QueryException $e) {
 				throw new OCSForbiddenException($this->l->t('Sharing %s failed because the back end does not support room shares', [$node->getPath()]));
 			}
 		} elseif ($shareType === IShare::TYPE_DECK) {
 			try {
-				$this->getDeckShareHelper()->createShare($share, $shareWith, $permissions, $expireDate);
+				$this->getDeckShareHelper()->createShare($share, $shareWith, $permissions, $expireDate ?? '');
 			} catch (QueryException $e) {
 				throw new OCSForbiddenException($this->l->t('Sharing %s failed because the back end does not support room shares', [$node->getPath()]));
 			}
 		} elseif ($shareType === IShare::TYPE_SCIENCEMESH) {
 			try {
-				$this->getSciencemeshShareHelper()->createShare($share, $shareWith, $permissions, $expireDate);
+				$this->getSciencemeshShareHelper()->createShare($share, $shareWith, $permissions, $expireDate ?? '');
 			} catch (QueryException $e) {
 				throw new OCSForbiddenException($this->l->t('Sharing %s failed because the back end does not support ScienceMesh shares', [$node->getPath()]));
 			}
diff --git a/apps/files_sharing/openapi.json b/apps/files_sharing/openapi.json
index 6808993af3f..f5a8ead3eba 100644
--- a/apps/files_sharing/openapi.json
+++ b/apps/files_sharing/openapi.json
@@ -1781,10 +1781,10 @@
                     {
                         "name": "expireDate",
                         "in": "query",
-                        "description": "Expiry date of the share using user timezone at 00:00. It means date in UTC timezone will be used.",
+                        "description": "The expiry date of the share in the user's timezone (UTC) at 00:00. If $expireDate is not supplied or set to `null`, the system default will be used.",
                         "schema": {
                             "type": "string",
-                            "default": ""
+                            "nullable": true
                         }
                     },
                     {
diff --git a/lib/private/Share20/Manager.php b/lib/private/Share20/Manager.php
index 27478a4f708..6e2cfe7ed39 100644
--- a/lib/private/Share20/Manager.php
+++ b/lib/private/Share20/Manager.php
@@ -348,26 +348,6 @@ class Manager implements IManager {
 
 		$expirationDate = $share->getExpirationDate();
 
-		if ($expirationDate !== null) {
-			$expirationDate->setTimezone($this->dateTimeZone->getTimeZone());
-			$expirationDate->setTime(0, 0, 0);
-
-			$date = new \DateTime('now', $this->dateTimeZone->getTimeZone());
-			$date->setTime(0, 0, 0);
-			if ($date >= $expirationDate) {
-				$message = $this->l->t('Expiration date is in the past');
-				throw new GenericShareException($message, $message, 404);
-			}
-		}
-
-		// If expiredate is empty set a default one if there is a default
-		$fullId = null;
-		try {
-			$fullId = $share->getFullId();
-		} catch (\UnexpectedValueException $e) {
-			// This is a new share
-		}
-
 		if ($isRemote) {
 			$defaultExpireDate = $this->shareApiRemoteDefaultExpireDate();
 			$defaultExpireDays = $this->shareApiRemoteDefaultExpireDays();
@@ -379,28 +359,53 @@ class Manager implements IManager {
 			$configProp = 'internal_defaultExpDays';
 			$isEnforced = $this->shareApiInternalDefaultExpireDateEnforced();
 		}
-		if ($fullId === null && $expirationDate === null && $defaultExpireDate) {
-			$expirationDate = new \DateTime('now', $this->dateTimeZone->getTimeZone());
-			$expirationDate->setTime(0, 0, 0);
-			$days = (int)$this->config->getAppValue('core', $configProp, (string)$defaultExpireDays);
-			if ($days > $defaultExpireDays) {
-				$days = $defaultExpireDays;
+
+		// If $expirationDate is falsy, noExpirationDate is true and expiration not enforced
+		// Then skip expiration date validation as null is accepted
+		if(!($share->getNoExpirationDate() && !$isEnforced)) {
+			if ($expirationDate != null) {
+				$expirationDate->setTimezone($this->dateTimeZone->getTimeZone());
+				$expirationDate->setTime(0, 0, 0);
+
+				$date = new \DateTime('now', $this->dateTimeZone->getTimeZone());
+				$date->setTime(0, 0, 0);
+				if ($date >= $expirationDate) {
+					$message = $this->l->t('Expiration date is in the past');
+					throw new GenericShareException($message, $message, 404);
+				}
 			}
-			$expirationDate->add(new \DateInterval('P' . $days . 'D'));
-		}
 
-		// If we enforce the expiration date check that is does not exceed
-		if ($isEnforced) {
-			if ($expirationDate === null) {
-				throw new \InvalidArgumentException('Expiration date is enforced');
+			// If expiredate is empty set a default one if there is a default
+			$fullId = null;
+			try {
+				$fullId = $share->getFullId();
+			} catch (\UnexpectedValueException $e) {
+				// This is a new share
 			}
 
-			$date = new \DateTime('now', $this->dateTimeZone->getTimeZone());
-			$date->setTime(0, 0, 0);
-			$date->add(new \DateInterval('P' . $defaultExpireDays . 'D'));
-			if ($date < $expirationDate) {
-				$message = $this->l->n('Cannot set expiration date more than %n day in the future', 'Cannot set expiration date more than %n days in the future', $defaultExpireDays);
-				throw new GenericShareException($message, $message, 404);
+			if ($fullId === null && $expirationDate === null && $defaultExpireDate) {
+				$expirationDate = new \DateTime('now', $this->dateTimeZone->getTimeZone());
+				$expirationDate->setTime(0, 0, 0);
+				$days = (int)$this->config->getAppValue('core', $configProp, (string)$defaultExpireDays);
+				if ($days > $defaultExpireDays) {
+					$days = $defaultExpireDays;
+				}
+				$expirationDate->add(new \DateInterval('P' . $days . 'D'));
+			}
+
+			// If we enforce the expiration date check that is does not exceed
+			if ($isEnforced) {
+				if (empty($expirationDate)) {
+					throw new \InvalidArgumentException('Expiration date is enforced');
+				}
+
+				$date = new \DateTime('now', $this->dateTimeZone->getTimeZone());
+				$date->setTime(0, 0, 0);
+				$date->add(new \DateInterval('P' . $defaultExpireDays . 'D'));
+				if ($date < $expirationDate) {
+					$message = $this->l->n('Cannot set expiration date more than %n day in the future', 'Cannot set expiration date more than %n days in the future', $defaultExpireDays);
+					throw new GenericShareException($message, $message, 404);
+				}
 			}
 		}
 
@@ -433,51 +438,57 @@ class Manager implements IManager {
 	 */
 	protected function validateExpirationDateLink(IShare $share) {
 		$expirationDate = $share->getExpirationDate();
-
-		if ($expirationDate !== null) {
-			$expirationDate->setTimezone($this->dateTimeZone->getTimeZone());
-			$expirationDate->setTime(0, 0, 0);
-
-			$date = new \DateTime('now', $this->dateTimeZone->getTimeZone());
-			$date->setTime(0, 0, 0);
-			if ($date >= $expirationDate) {
-				$message = $this->l->t('Expiration date is in the past');
-				throw new GenericShareException($message, $message, 404);
+		$isEnforced = $this->shareApiLinkDefaultExpireDateEnforced();
+
+		// If $expirationDate is falsy, noExpirationDate is true and expiration not enforced
+		// Then skip expiration date validation as null is accepted
+		if(!($share->getNoExpirationDate() && !$isEnforced)) {
+			if ($expirationDate !== null) {
+				$expirationDate->setTimezone($this->dateTimeZone->getTimeZone());
+				$expirationDate->setTime(0, 0, 0);
+	
+				$date = new \DateTime('now', $this->dateTimeZone->getTimeZone());
+				$date->setTime(0, 0, 0);
+				if ($date >= $expirationDate) {
+					$message = $this->l->t('Expiration date is in the past');
+					throw new GenericShareException($message, $message, 404);
+				}
 			}
-		}
-
-		// If expiredate is empty set a default one if there is a default
-		$fullId = null;
-		try {
-			$fullId = $share->getFullId();
-		} catch (\UnexpectedValueException $e) {
-			// This is a new share
-		}
 
-		if ($fullId === null && $expirationDate === null && $this->shareApiLinkDefaultExpireDate()) {
-			$expirationDate = new \DateTime('now', $this->dateTimeZone->getTimeZone());
-			$expirationDate->setTime(0, 0, 0);
-
-			$days = (int)$this->config->getAppValue('core', 'link_defaultExpDays', (string)$this->shareApiLinkDefaultExpireDays());
-			if ($days > $this->shareApiLinkDefaultExpireDays()) {
-				$days = $this->shareApiLinkDefaultExpireDays();
+			// If expiredate is empty set a default one if there is a default
+			$fullId = null;
+			try {
+				$fullId = $share->getFullId();
+			} catch (\UnexpectedValueException $e) {
+				// This is a new share
+			}
+	
+			if ($fullId === null && $expirationDate === null && $this->shareApiLinkDefaultExpireDate()) {
+				$expirationDate = new \DateTime('now', $this->dateTimeZone->getTimeZone());
+				$expirationDate->setTime(0, 0, 0);
+	
+				$days = (int)$this->config->getAppValue('core', 'link_defaultExpDays', (string)$this->shareApiLinkDefaultExpireDays());
+				if ($days > $this->shareApiLinkDefaultExpireDays()) {
+					$days = $this->shareApiLinkDefaultExpireDays();
+				}
+				$expirationDate->add(new \DateInterval('P' . $days . 'D'));
 			}
-			$expirationDate->add(new \DateInterval('P' . $days . 'D'));
-		}
-
-		// If we enforce the expiration date check that is does not exceed
-		if ($this->shareApiLinkDefaultExpireDateEnforced()) {
-			if ($expirationDate === null) {
-				throw new \InvalidArgumentException('Expiration date is enforced');
+	
+			// If we enforce the expiration date check that is does not exceed
+			if ($isEnforced) {
+				if (empty($expirationDate)) {
+					throw new \InvalidArgumentException('Expiration date is enforced');
+				}
+	
+				$date = new \DateTime('now', $this->dateTimeZone->getTimeZone());
+				$date->setTime(0, 0, 0);
+				$date->add(new \DateInterval('P' . $this->shareApiLinkDefaultExpireDays() . 'D'));
+				if ($date < $expirationDate) {
+					$message = $this->l->n('Cannot set expiration date more than %n day in the future', 'Cannot set expiration date more than %n days in the future', $this->shareApiLinkDefaultExpireDays());
+					throw new GenericShareException($message, $message, 404);
+				}
 			}
 
-			$date = new \DateTime('now', $this->dateTimeZone->getTimeZone());
-			$date->setTime(0, 0, 0);
-			$date->add(new \DateInterval('P' . $this->shareApiLinkDefaultExpireDays() . 'D'));
-			if ($date < $expirationDate) {
-				$message = $this->l->n('Cannot set expiration date more than %n day in the future', 'Cannot set expiration date more than %n days in the future', $this->shareApiLinkDefaultExpireDays());
-				throw new GenericShareException($message, $message, 404);
-			}
 		}
 
 		$accepted = true;
diff --git a/lib/private/Share20/Share.php b/lib/private/Share20/Share.php
index 19b36cb60e8..897709ee028 100644
--- a/lib/private/Share20/Share.php
+++ b/lib/private/Share20/Share.php
@@ -99,10 +99,11 @@ class Share implements IShare {
 
 	/** @var ICacheEntry|null */
 	private $nodeCacheEntry;
-
 	/** @var bool */
 	private $hideDownload = false;
 
+	private bool $noExpirationDate = false;
+
 	public function __construct(IRootFolder $rootFolder, IUserManager $userManager) {
 		$this->rootFolder = $rootFolder;
 		$this->userManager = $userManager;
@@ -425,6 +426,21 @@ class Share implements IShare {
 		return $this->expireDate;
 	}
 
+	/**
+	 * @inheritdoc
+	 */
+	public function setNoExpirationDate(bool $noExpirationDate) {
+		$this->noExpirationDate = $noExpirationDate;
+		return $this;
+	}
+
+	/**
+	 * @inheritdoc
+	 */
+	public function getNoExpirationDate(): bool {
+		return $this->noExpirationDate;
+	}
+
 	/**
 	 * @inheritdoc
 	 */
diff --git a/lib/public/Share/IShare.php b/lib/public/Share/IShare.php
index a059696a75e..d2d5eabe6ec 100644
--- a/lib/public/Share/IShare.php
+++ b/lib/public/Share/IShare.php
@@ -385,20 +385,38 @@ interface IShare {
 	/**
 	 * Set the expiration date
 	 *
-	 * @param null|\DateTime $expireDate
+	 * @param \DateTime|null $expireDate
 	 * @return \OCP\Share\IShare The modified object
 	 * @since 9.0.0
 	 */
-	public function setExpirationDate($expireDate);
+	public function setExpirationDate(\DateTime|null $expireDate);
 
 	/**
 	 * Get the expiration date
 	 *
-	 * @return null|\DateTime
+	 * @return \DateTime|null
 	 * @since 9.0.0
 	 */
 	public function getExpirationDate();
 
+	/**
+	 * Set overwrite flag for falsy expiry date vavlues
+	 *
+	 * @param bool $noExpirationDate
+	 * @return \OCP\Share\IShare The modified object
+	 * @since 29.0.1
+	 */
+	public function setNoExpirationDate(bool $noExpirationDate);
+
+
+	/**
+	 * Get value of overwrite falsy expiry date flag
+	 *
+	 * @return bool
+	 * @since 29.0.1
+	 */
+	public function getNoExpirationDate();
+
 	/**
 	 * Is the share expired ?
 	 *