SharePoint: Change Term Set Owner using PowerShell via CSOM

SCRIPT

Param (
    [Parameter(Mandatory=$True)]
    [string]$Url,
    [Parameter(Mandatory=$True)]
    [string]$NewOwner,
    [Parameter(Mandatory=$True)]
    [string]$TermGroupName,
    [Parameter(Mandatory=$True)]
    [string]$TermSetName,
    [Parameter(Mandatory=$True)]
    [string]$AdminUsername
)
[System.Reflection.Assembly]::LoadWithPartialName("Microsoft.SharePoint.Client")
[System.Reflection.Assembly]::LoadWithPartialName("Microsoft.SharePoint.Client.Runtime")
[System.Reflection.Assembly]::LoadWithPartialName("Microsoft.SharePoint.Client.Taxonomy")
$lcid = "1033"
Write-Host "Please enter password for $($Url):"
$pwd = Read-Host -AsSecureString
# connect/authenticate to SharePoint Online and get ClientContext object..
$sCtx = New-Object Microsoft.SharePoint.Client.ClientContext($Url)
$sCredentials = New-Object Microsoft.SharePoint.Client.SharePointOnlineCredentials($AdminUsername, $pwd)
$sCtx.Credentials = $sCredentials
if (!$sCtx.ServerObjectIsNull.Value)
{
    Write-Host "Connected to SharePoint Online: " $sCtx.Url "" -ForegroundColor Green
    $sTaxonomySession = [Microsoft.SharePoint.Client.Taxonomy.TaxonomySession]::GetTaxonomySession($sCtx)
    $sTaxonomySession.UpdateCache()
    $sCtx.Load($sTaxonomySession)
    $sCtx.ExecuteQuery()
    if (!$sTaxonomySession.ServerObjectIsNull)
    {
        Write-Host "Taxonomy session: " $sTaxonomySession.Path.Identity "" -ForegroundColor Green
        $sTermStore = $sTaxonomySession.GetDefaultSiteCollectionTermStore()
        $sCtx.Load($sTermStore)
        $sCtx.ExecuteQuery()
        if ($sTermStore.IsOnline)
        {
            Write-Host "Term Store connected:" $sTermStore.Id "" -ForegroundColor Green
            $sCtx.Load($sTermStore.Groups)
            $sCtx.ExecuteQuery()
            foreach ($sTermGroup in $sTermStore.Groups)
            {
                if ($sTermGroup.Name -eq $TermGroupName)
                {
                    Write-Host "Term Group: " $sTermGroup.Name "-" $sTermGroup.Id "" -ForegroundColor Green
                    $termSets = $sTermGroup.TermSets
                    $sCtx.Load($termSets)
                    $sCtx.ExecuteQuery()
                    $termSet = $termSets.GetByName($TermSetName)
                    $sCtx.Load($termSet)
                    $sCtx.ExecuteQuery()
                        Write-Host "Term Set found: " $termSet.Name ", Current Owner: " $termSet.Owner "" -ForegroundColor Green
                        $termSet.Owner = $NewOwner
                         Write-Host "Owner changed to: " $NewOwner "" -ForegroundColor Cyan
                }
            }
            Write-Host "Committing..." -ForegroundColor Cyan
            $sTermStore.CommitAll()
            $sCtx.ExecuteQuery()
            Write-Host "Done!" -ForegroundColor Green
        }
    }
}

USAGE

.\ChangeTermSetOwner.ps1 -Url https://myspsite.sharepoint.com -NewOwner newowner@myspsite.com -TermGroupName MyTermGroup -TermSetName MyTermSet -AdminUsername adminusername@myspsite.com