Well in that case you are not allowing Scripture to be the final criterion. Kindly read and study Revelation 13 carefully:
WORLDWIDE WORSHIP OF SATAN AND THE ANTICHRIST
3 And I saw one of his heads as it were wounded to death; and his deadly wound was healed: and all the world wondered after the beast. 4 And they worshipped the dragon which gave power unto the beast: and they worshipped the beast, saying, Who is like unto the beast? who is able to make war with him?...8 And all that dwell upon the earth shall worship him, whose names are not written in the book of life of the Lamb slain from the foundation of the world.
WORLDWIDE POWER GIVEN TO THE ANTICHRIST
7 And it was given unto him to make war with the saints, and to overcome them: and power was given him over all kindreds, and tongues, and nations.
WORLDWIDE APPLICATION OF THE MARK OF THE BEAST
11 And I beheld another beast coming up out of the earth; and he had two horns like a lamb, and he spake as a dragon.12 And he exerciseth all the power of the first beast before him, and causeth the earth and them which dwell therein to worship the first beast, whose deadly wound was healed... 16 And he causeth all, both small and great, rich and poor, free and bond, to receive a mark in their right hand, or in their foreheads: 17 And that no man might buy or sell, save he that had the mark, or the name of the beast, or the number of his name.
The idea that the "mark of the beast" must be a literal, physical mark on the hand or forehead is just not consistent with scripture itself.
As we know, Revelation is a book that delves back into the OT for its images and references. Look in Deut 6:
You shall love the LORD your God with all your heart and with all your soul and with all your might. And these words that I command you today shall be on your heart. You shall teach them diligently to your children, and shall talk of them when you sit in your house, and when you walk by the way, and when you lie down, and when you rise. You shall bind them as a sign on your hand, and they shall be as frontlets between your eyes. You shall write them on the doorposts of your house and on your gates. -Deuteronomy 6:5–9
Moses is speaking here of how we are to take to heart and apply God's laws. We know that some devout Jews took this passage rather too literally and began wearing tiny books on their forehead. Most people will recognize that they have over-literalized what Deuteronomy is speaking of here. We are to diligently take into our minds and into our doings...the works of our hands and hearts...the Word of God. Hence we also find later in the OT the promise of God to "write his law upon our hearts".
So, when we come to Revelation, a book that is so full to flowing with references and images pulled from the OT, it is nonsense in the same order of wearing little books on our foreheads, to think "a-ha! It HAS to be a tatto, or chip!" No...the most rational and logical thing in this instance, is to look back to where God has previously used such a phrase before...and what it meant there.
To take the 'mark' of the beast is to subscribe to Satan's lawlessness, his rebellion against God. To live, both mind and deed, for oneself or for evil, rather than for God.
And to support this further, we can see that in Revelation to have "the seal of God" on a believers forehead, is to have the Holy Spirit...something that we are told we are 'sealed' with in Eph 1:13. And indeed, we know that when we recieve this mark of salvation we have no physical mark, but an inner one, where we begin to live, both thought and deed, in accordance with God's will.
There are many, as I've pointed out above, reasons to believe the Mark of the Beast is not physical, and only speculation to believe it must be. One can only hide behind claims of a 'literal' reading of Revelation for so long before said literal reading actually comes to the defense of other interpretations. When the book itself launches itself by declaring it to be a book of images and symbols, and it then goes on to refer back to the OT more often than any other book in the NT, it becomes rather futile to then ignore what the OT says about those references, but instead start making up your own conclusions of those images.