diff --git a/block.go b/block.go
index 74e89a6..b2d6596 100644
--- a/block.go
+++ b/block.go
@@ -2,7 +2,9 @@ package proton
 
 import (
 	"context"
+	"fmt"
 	"io"
+	"net/http"
 
 	"github.com/go-resty/resty/v2"
 )
@@ -33,10 +35,40 @@ func (c *Client) RequestBlockUpload(ctx context.Context, req BlockUploadReq) ([]
 }
 
 func (c *Client) UploadBlock(ctx context.Context, bareURL, token string, block io.Reader) error {
-	return c.do(ctx, func(r *resty.Request) (*resty.Response, error) {
-		return r.
-			SetHeader("pm-storage-token", token).
-			SetMultipartField("Block", "blob", "application/octet-stream", block).
-			Post(bareURL)
-	})
+	// Storage servers require only pm-storage-token, not API auth headers.
+	// Use a plain resty request instead of going through c.do() which adds
+	// x-pm-uid and Authorization headers.
+	req := resty.New().R().SetContext(ctx)
+	req.SetHeader("pm-storage-token", token)
+	req.SetMultipartField("Block", "blob", "application/octet-stream", block)
+
+	resp, err := req.Post(bareURL)
+	if err != nil {
+		return err
+	}
+
+	if resp.StatusCode() != http.StatusOK {
+		return fmt.Errorf("%v POST %s: %s", resp.StatusCode(), bareURL, resp.String())
+	}
+
+	return nil
 }
+
+func (c *Client) GetUploadVerification(ctx context.Context, volumeID, linkID, revisionID string) (UploadVerification, error) {
+	var res struct {
+		VerificationCode string
+		ContentKeyPacket string
+	}
+
+	route := fmt.Sprintf("/drive/v2/volumes/%s/links/%s/revisions/%s/verification", volumeID, linkID, revisionID)
+	if err := c.do(ctx, func(r *resty.Request) (*resty.Response, error) {
+		return r.SetResult(&res).Get(route)
+	}); err != nil {
+		return UploadVerification{}, err
+	}
+
+	return UploadVerification{
+		VerificationCode: res.VerificationCode,
+		ContentKeyPacket: res.ContentKeyPacket,
+	}, nil
+}
\ No newline at end of file
diff --git a/block_types.go b/block_types.go
index ad41611..0eb5288 100644
--- a/block_types.go
+++ b/block_types.go
@@ -19,6 +19,7 @@ type BlockUploadReq struct {
 	ShareID    string
 	LinkID     string
 	RevisionID string
+	VolumeID   string
 
 	BlockList []BlockUploadInfo
 }
@@ -28,6 +29,16 @@ type BlockUploadInfo struct {
 	Size         int64
 	EncSignature string
 	Hash         string
+	Verifier     *BlockVerifier `json:"Verifier,omitempty"`
+}
+
+type BlockVerifier struct {
+	Token string
+}
+
+type UploadVerification struct {
+	VerificationCode string
+	ContentKeyPacket string
 }
 
 type BlockUploadLink struct {