diff --git a/cmd/erasure-server-pool-multipart-initiate_test.go b/cmd/erasure-server-pool-multipart-initiate_test.go
new file mode 100644
index 000000000..c4f81c893
--- /dev/null
+++ b/cmd/erasure-server-pool-multipart-initiate_test.go
@@ -0,0 +1,194 @@
+// Copyright (c) 2026 Denis Babchuk
+//
+// This file is part of Silo Object Storage stack
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Affero General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Affero General Public License for more details.
+//
+// You should have received a copy of the GNU Affero General Public License
+// along with this program. If not, see <http://www.gnu.org/licenses/>.
+
+package cmd
+
+import (
+	"fmt"
+	"net/http"
+	"slices"
+	"strings"
+	"testing"
+	"time"
+
+	xhttp "github.com/minio/minio/internal/http"
+)
+
+// multipartInitiateUploads returns the number of pending uploads of object in
+// each pool.
+func multipartInitiateUploads(t *testing.T, z *erasureServerPools, bucket, object string) []int {
+	t.Helper()
+	counts := make([]int, len(z.serverPools))
+	for i, pool := range z.serverPools {
+		res, err := pool.listMultipartUploadsExact(t.Context(), bucket, object)
+		if err != nil {
+			t.Fatal(err)
+		}
+		counts[i] = len(res.Uploads)
+	}
+	return counts
+}
+
+// A multi-pool NewMultipartUpload goes to the pool of a pending upload of the
+// key or, without one, to the pool chosen by capacity. Neither has to hold the
+// current object, so a condition sent with the initiate must be evaluated
+// against the current object across pools, as for PUT and completion.
+// Routing itself does not change: an accepted upload lands in the same pool.
+// Allocation follows a current delete marker to its pool, so a stale version
+// under a marker in another pool is reached only through a pending upload.
+func TestPoolsMultipartConditionalInitiateHTTP(t *testing.T) {
+	const wrongETag = "ffffffffffffffffffffffffffffffff"
+	for _, mode := range []string{"unversioned", "versioned"} {
+		t.Run(mode, func(t *testing.T) {
+			z, _ := consistencyPools(t)
+			bucket, router := conditionalPutBucket(t, z, mode)
+			versioned := mode == "versioned"
+			for _, route := range []string{"pending-upload", "allocation"} {
+				for target := range 2 {
+					for _, layout := range []string{"current-in-other-pool", "stale-copy-in-target", "marker-in-other-pool", "control-current-in-target"} {
+						if layout == "marker-in-other-pool" && (!versioned || route == "allocation") {
+							continue
+						}
+						for _, cond := range []string{"if-match-current", "if-match-any", "if-match-stale", "if-none-match-any"} {
+							t.Run(fmt.Sprintf("%s/target=%d/%s/%s", route, target, layout, cond), func(t *testing.T) {
+								object := fmt.Sprintf("%s-%d-%s-%s", route, target, layout, cond)
+								other := 1 - target
+								opts := func(age time.Duration) ObjectOptions {
+									return ObjectOptions{Versioned: versioned, MTime: UTCNow().Add(-age)}
+								}
+								present, staleETag := true, wrongETag
+								var current ObjectInfo
+								switch layout {
+								case "current-in-other-pool":
+									current = putConsistencyObject(t, z, bucket, object, other, "current", opts(time.Minute))
+								case "stale-copy-in-target":
+									staleETag = putConsistencyObject(t, z, bucket, object, target, "stale", opts(time.Hour)).ETag
+									current = putConsistencyObject(t, z, bucket, object, other, "current", opts(time.Minute))
+								case "marker-in-other-pool":
+									// The client knows the version under the marker.
+									current = putConsistencyObject(t, z, bucket, object, target, "deleted", opts(time.Hour))
+									if _, err := z.serverPools[other].DeleteObject(t.Context(), bucket, object, ObjectOptions{Versioned: true, VersionID: mustGetUUID(), DeleteMarker: true, MTime: UTCNow().Add(-time.Minute)}); err != nil {
+										t.Fatal(err)
+									}
+									present = false
+								case "control-current-in-target":
+									staleETag = putConsistencyObject(t, z, bucket, object, other, "stale", opts(time.Hour)).ETag
+									current = putConsistencyObject(t, z, bucket, object, target, "current", opts(time.Minute))
+								}
+
+								before := make([]int, len(z.serverPools))
+								if route == "pending-upload" {
+									if _, err := z.serverPools[target].NewMultipartUpload(t.Context(), bucket, object, ObjectOptions{Versioned: versioned}); err != nil {
+										t.Fatal(err)
+									}
+									before[target] = 1
+								} else {
+									defer conditionalPutPool(t, z, object, target)()
+									if idx, err := z.getWritePoolIdx(t.Context(), bucket, object, -1, false); err != nil || idx != target {
+										t.Fatalf("allocation target=%d: idx=%d err=%v", target, idx, err)
+									}
+								}
+
+								var headers map[string]string
+								switch cond {
+								case "if-match-current":
+									headers = map[string]string{xhttp.IfMatch: fmt.Sprintf("%q", current.ETag)}
+								case "if-match-any":
+									headers = map[string]string{xhttp.IfMatch: "*"}
+								case "if-match-stale":
+									headers = map[string]string{xhttp.IfMatch: fmt.Sprintf("%q", staleETag)}
+								case "if-none-match-any":
+									headers = map[string]string{xhttp.IfNoneMatch: "*"}
+								}
+								want := http.StatusOK
+								switch {
+								case !present && strings.HasPrefix(cond, "if-match"):
+									want = http.StatusNotFound
+								case !present:
+								case cond == "if-match-stale", cond == "if-none-match-any":
+									want = http.StatusPreconditionFailed
+								}
+
+								rec := multipartConditionRequest(t, router, http.MethodPost, getNewMultipartURL("", bucket, object), "", headers)
+								after := multipartInitiateUploads(t, z, bucket, object)
+								t.Logf("initiate %v: HTTP %d, uploads per pool %v -> %v", headers, rec.Code, before, after)
+								if rec.Code != want {
+									t.Errorf("initiate HTTP %d, want %d: %s", rec.Code, want, rec.Body.String())
+								}
+								wantAfter := slices.Clone(before)
+								if want == http.StatusOK {
+									wantAfter[target]++
+								}
+								if !slices.Equal(after, wantAfter) {
+									t.Errorf("uploads per pool %v, want %v", after, wantAfter)
+								}
+								if rec.Code != want {
+									return
+								}
+								switch want {
+								case http.StatusPreconditionFailed:
+									multipartConditionError(t, rec, "PreconditionFailed")
+									if etag := multipartConditionResponseETag(rec); etag != current.ETag {
+										t.Errorf("412 describes ETag %s, want the current %s", etag, current.ETag)
+									}
+								case http.StatusNotFound:
+									multipartConditionError(t, rec, "NoSuchKey")
+								}
+							})
+						}
+					}
+				}
+			}
+		})
+	}
+}
+
+// A pool that cannot be read may hold the newest object, so the condition
+// cannot be evaluated even when the upload goes to a readable pool.
+func TestPoolsMultipartConditionalInitiateUnreadable(t *testing.T) {
+	z, _ := consistencyPools(t)
+	bucket, router := conditionalPutBucket(t, z, "unversioned")
+	for faultPool := range 2 {
+		for _, match := range []bool{false, true} {
+			t.Run(fmt.Sprintf("fault-pool=%d/match=%t", faultPool, match), func(t *testing.T) {
+				object := fmt.Sprintf("unreadable-%d-%t", faultPool, match)
+				putConsistencyObject(t, z, bucket, object, 0, "stale", ObjectOptions{MTime: UTCNow().Add(-time.Hour)})
+				putConsistencyObject(t, z, bucket, object, 1, "current", ObjectOptions{MTime: UTCNow().Add(-time.Minute)})
+				defer conditionalPutPool(t, z, object, 0)()
+				defer conditionalPutSwapDisks(z.serverPools[faultPool], object, func(disk StorageAPI) StorageAPI {
+					return consistencyReadFaultDisk{StorageAPI: disk, bucket: bucket, object: object}
+				})()
+				headers := map[string]string{xhttp.IfNoneMatch: "*"}
+				if match {
+					headers = map[string]string{xhttp.IfMatch: "*"}
+				}
+				rec := multipartConditionRequest(t, router, http.MethodPost, getNewMultipartURL("", bucket, object), "", headers)
+				if rec.Code != http.StatusServiceUnavailable {
+					t.Errorf("unverified initiate must fail: HTTP %d: %s", rec.Code, rec.Body.String())
+				}
+				called := 0
+				_, err := z.NewMultipartUpload(t.Context(), bucket, object, ObjectOptions{HasIfMatch: match, CheckPrecondFn: func(ObjectInfo) bool { called++; return false }})
+				if !isErrReadQuorum(err) || called != 0 {
+					t.Errorf("initiate error=%v, callback calls=%d", err, called)
+				}
+				if n := multipartInitiateUploads(t, z, bucket, object); !slices.Equal(n, []int{0, 0}) {
+					t.Errorf("uploads per pool %v after failed initiates", n)
+				}
+			})
+		}
+	}
+}