diff --git a/src/dependencies.py b/src/dependencies.py
index 384c7c9..e9e178d 100644
--- a/src/dependencies.py
+++ b/src/dependencies.py
@@ -2,6 +2,10 @@
 from typing import Annotated
 from fastapi import Depends, HTTPException, Request
 from sqlalchemy.ext.asyncio import AsyncSession
+from typing import List, Optional
+from itertools import chain
+
+from fastapi import Query
 
 from entities.engine import get_session
 from entities.repos import institutions_repo as repo
@@ -35,3 +39,18 @@ def request_needs_domain_check(request: Request) -> bool:
 
 async def email_domain_denied(session: AsyncSession, email: str) -> bool:
     return not await repo.is_email_domain_allowed(session, email)
+
+
+def parse_leis(leis: List[str] = Query(None)) -> Optional[List]:
+    """
+    Parses leis from list of one or multiple strings to a list of
+    multiple distinct lei strings.
+    Returns empty list when nothing is passed in
+    Ex1: ['lei1,lei2'] -> ['lei1', 'lei2']
+    Ex2: ['lei1,lei2', 'lei3,lei4'] -> ['lei1','lei2','lei3','lei4']
+    """
+
+    if leis:
+        return list(chain.from_iterable([x.split(",") for x in leis]))
+    else:
+        return None
diff --git a/src/entities/repos/institutions_repo.py b/src/entities/repos/institutions_repo.py
index 887809b..fb7ef88 100644
--- a/src/entities/repos/institutions_repo.py
+++ b/src/entities/repos/institutions_repo.py
@@ -14,7 +14,11 @@
 
 
 async def get_institutions(
-    session: AsyncSession, domain: str = "", page: int = 0, count: int = 100
+    session: AsyncSession,
+    leis: List[str] = None,
+    domain: str = "",
+    page: int = 0,
+    count: int = 100,
 ) -> List[FinancialInstitutionDao]:
     async with session.begin():
         stmt = (
@@ -23,7 +27,9 @@ async def get_institutions(
             .limit(count)
             .offset(page * count)
         )
-        if d := domain.strip():
+        if leis:
+            stmt = stmt.filter(FinancialInstitutionDao.lei.in_(leis))
+        elif d := domain.strip():
             search = "%{}%".format(d)
             stmt = stmt.join(
                 FinancialInstitutionDomainDao,
diff --git a/src/routers/institutions.py b/src/routers/institutions.py
index e54ed32..440ca13 100644
--- a/src/routers/institutions.py
+++ b/src/routers/institutions.py
@@ -2,6 +2,7 @@
 from http import HTTPStatus
 from oauth2 import oauth2_admin
 from util import Router
+from dependencies import parse_leis
 from typing import Annotated, List, Tuple
 from entities.engine import get_session
 from entities.repos import institutions_repo as repo
@@ -28,11 +29,14 @@ async def set_db(
 @requires("authenticated")
 async def get_institutions(
     request: Request,
+    leis: List[str] = Depends(parse_leis),
     domain: str = "",
     page: int = 0,
     count: int = 100,
 ):
-    return await repo.get_institutions(request.state.db_session, domain, page, count)
+    return await repo.get_institutions(
+        request.state.db_session, leis, domain, page, count
+    )
 
 
 @router.post("/", response_model=Tuple[str, FinancialInstitutionDto])
diff --git a/tests/entities/repos/test_institutions_repo.py b/tests/entities/repos/test_institutions_repo.py
index f042c7f..584fd31 100644
--- a/tests/entities/repos/test_institutions_repo.py
+++ b/tests/entities/repos/test_institutions_repo.py
@@ -16,22 +16,29 @@ async def setup(
         self,
         transaction_session: AsyncSession,
     ):
-        fi_dao = FinancialInstitutionDao(
+        fi_dao_123, fi_dao_456 = FinancialInstitutionDao(
             name="Test Bank 123",
             lei="TESTBANK123",
             domains=[
-                FinancialInstitutionDomainDao(domain="test.bank", lei="TESTBANK123")
+                FinancialInstitutionDomainDao(domain="test.bank.1", lei="TESTBANK123")
+            ],
+        ), FinancialInstitutionDao(
+            name="Test Bank 456",
+            lei="TESTBANK456",
+            domains=[
+                FinancialInstitutionDomainDao(domain="test.bank.2", lei="TESTBANK456")
             ],
         )
-        transaction_session.add(fi_dao)
+        transaction_session.add(fi_dao_123)
+        transaction_session.add(fi_dao_456)
         await transaction_session.commit()
 
     async def test_get_institutions(self, query_session: AsyncSession):
         res = await repo.get_institutions(query_session)
-        assert len(res) == 1
+        assert len(res) == 2
 
     async def test_get_institutions_by_domain(self, query_session: AsyncSession):
-        res = await repo.get_institutions(query_session, domain="test.bank")
+        res = await repo.get_institutions(query_session, domain="test.bank.1")
         assert len(res) == 1
 
     async def test_get_institutions_by_domain_not_existing(
@@ -40,13 +47,25 @@ async def test_get_institutions_by_domain_not_existing(
         res = await repo.get_institutions(query_session, domain="testing.bank")
         assert len(res) == 0
 
+    async def test_get_institutions_by_lei_list(self, query_session: AsyncSession):
+        res = await repo.get_institutions(
+            query_session, leis=["TESTBANK123", "TESTBANK456"]
+        )
+        assert len(res) == 2
+
+    async def test_get_institutions_by_lei_list_item_not_existing(
+        self, query_session: AsyncSession
+    ):
+        res = await repo.get_institutions(query_session, leis=["NOTTESTBANK"])
+        assert len(res) == 0
+
     async def test_add_institution(self, transaction_session: AsyncSession):
         await repo.upsert_institution(
             transaction_session,
             FinancialInstitutionDao(name="New Bank 123", lei="NEWBANK123"),
         )
         res = await repo.get_institutions(transaction_session)
-        assert len(res) == 2
+        assert len(res) == 3
 
     async def test_update_institution(self, transaction_session: AsyncSession):
         await repo.upsert_institution(
@@ -54,7 +73,7 @@ async def test_update_institution(self, transaction_session: AsyncSession):
             FinancialInstitutionDao(name="Test Bank 234", lei="TESTBANK123"),
         )
         res = await repo.get_institutions(transaction_session)
-        assert len(res) == 1
+        assert len(res) == 2
         assert res[0].name == "Test Bank 234"
 
     async def test_add_domains(